[BUG] customization-class doesn't work when generating java SDK

### API Spec link

https://github.com/Azure/azure-rest-api-specs/tree/main/specification/healthdataaiservices/HealthDataAIServices.DeidServices

### API Spec version

latest

### Describe the bug

I need to override the generated java SDK code because of an Autorest [bug](https://github.com/Azure/autorest.java/pull/2854): but the customization doesn't work.

I am getting the following error:
```bash
Exception in thread "main" java.lang.RuntimeException: Failed to complete postprocessing. ]
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:111)
at com.azure.typespec.Main.handleDPG(Main.java:169)
at com.azure.typespec.Main.main(Main.java:116)
Caused by: java.lang.RuntimeException: Unable to complete customization
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:104)
... 2 more
Caused by: java.lang.RuntimeException: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.customization.Customization.run(Customization.java:52)
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:101)
... 2 more
Caused by: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:352)
at com.azure.autorest.extension.base.jsonrpc.Connection.requestWithSerializedObject(Connection.java:519)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.sendRequest(EclipseLanguageClient.java:219)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.initialize(EclipseLanguageClient.java:124)
at com.azure.autorest.customization.Customization.run(Customization.java:47)
... 3 more
Suppressed: java.lang.RuntimeException: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.close(EclipseLanguageClient.java:213)
at com.azure.autorest.customization.Customization.run(Customization.java:45)
... 3 more
Caused by: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:352)
at com.azure.autorest.extension.base.jsonrpc.Connection.request(Connection.java:465)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.close(EclipseLanguageClient.java:208)
... 4 more
Caused by: java.io.IOException: The pipe is being closed
at java.base/java.io.FileOutputStream.writeBytes(Native Method)
at java.base/java.io.FileOutputStream.write(FileOutputStream.java:367)
at java.base/java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:125)
at java.base/java.io.BufferedOutputStream.implFlush(BufferedOutputStream.java:252)
at java.base/java.io.BufferedOutputStream.flush(BufferedOutputStream.java:240)
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:350)
... 6 more
Caused by: java.io.IOException: The pipe is being closed
at java.base/java.io.FileOutputStream.writeBytes(Native Method)
at java.base/java.io.FileOutputStream.write(FileOutputStream.java:367)
at java.base/java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:125)
at java.base/java.io.BufferedOutputStream.implFlush(BufferedOutputStream.java:252)
at java.base/java.io.BufferedOutputStream.flush(BufferedOutputStream.java:240)
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:350)
... 7 more
Emitter "@azure-tools/typespec-java" crashed! This is a bug.
Please file an issue at https://github.com/Azure/autorest.java/issues

Error: JAR ended with code '1'.
at ChildProcess. (file:///C:/Users/daszanis/WORK/REPO/sdk-repos/sdk-repos/azure-sdk-for-java/sdk/healthdataaiservices/azure-health-deidentification/TempTypeSpecFiles/HealthDataAIServices.DeidServices/node_modules/@azure-tools/typespec-java/dist/src/emitter.js:123:37)
at ChildProcess.emit (node:events:517:28)
at ChildProcess._handle.onexit (node:internal/child_process:292:12)

--------------------------------------------------
Library Version 0.18.1
TypeSpec Compiler Version 0.58.0
Write-Error: C:\Users\daszanis\WORK\REPO\sdk-repos\azure-rest-api-specs\eng\scripts\TypeSpec-Generate-Sdk.ps1:92
Line |
92 | . $commonScript -TypeSpecProjectDirectory $TypeSpecProjectDirecto …
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| Failed to generate sdk project at
| C:\Users\daszanis\WORK\REPO\sdk-repos\sdk-repos\azure-sdk-for-java\sdk\healthdataaiservices\azure-health-deidentification
```

This is my related tsp config:
```yaml
"@azure-tools/typespec-java":
package-dir: "azure-health-deidentification"
customization-class: "customization/src/main/java/HealthDeidentificationSdkCustomization.java"
namespace: "com.azure.health.deidentification"
flavor: azure
```

My customization class is at [`sdk/healthdataaiservices/azure-health-deidentification/customization/src/main/java/HealthDeidentificationSdkCustomization.java`](https://github.com/danielszaniszlo/azure-sdk-for-java/blob/daszanis/feature/sdk-for-health-deid/sdk/healthdataaiservices/azure-health-deidentification/customization/src/main/java/HealthDeidentificationSdkCustomization.java)

Without the `customization-class` SDK generates without error.

### Expected behavior

The SDK generates successfully with customization.

### Actual behavior

I get the error message
```bash
Exception in thread "main" java.lang.RuntimeException: Failed to complete postprocessing. ]
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:111)
at com.azure.typespec.Main.handleDPG(Main.java:169)
at com.azure.typespec.Main.main(Main.java:116)
Caused by: java.lang.RuntimeException: Unable to complete customization
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:104)
... 2 more
Caused by: java.lang.RuntimeException: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.customization.Customization.run(Customization.java:52)
at com.azure.autorest.postprocessor.Postprocessor.postProcess(Postprocessor.java:101)
... 2 more
Caused by: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:352)
at com.azure.autorest.extension.base.jsonrpc.Connection.requestWithSerializedObject(Connection.java:519)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.sendRequest(EclipseLanguageClient.java:219)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.initialize(EclipseLanguageClient.java:124)
at com.azure.autorest.customization.Customization.run(Customization.java:47)
... 3 more
Suppressed: java.lang.RuntimeException: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.close(EclipseLanguageClient.java:213)
at com.azure.autorest.customization.Customization.run(Customization.java:45)
... 3 more
Caused by: java.lang.RuntimeException: java.io.IOException: The pipe is being closed
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:352)
at com.azure.autorest.extension.base.jsonrpc.Connection.request(Connection.java:465)
at com.azure.autorest.customization.implementation.ls.EclipseLanguageClient.close(EclipseLanguageClient.java:208)
... 4 more
Caused by: java.io.IOException: The pipe is being closed
at java.base/java.io.FileOutputStream.writeBytes(Native Method)
at java.base/java.io.FileOutputStream.write(FileOutputStream.java:367)
at java.base/java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:125)
at java.base/java.io.BufferedOutputStream.implFlush(BufferedOutputStream.java:252)
at java.base/java.io.BufferedOutputStream.flush(BufferedOutputStream.java:240)
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:350)
... 6 more
Caused by: java.io.IOException: The pipe is being closed
at java.base/java.io.FileOutputStream.writeBytes(Native Method)
at java.base/java.io.FileOutputStream.write(FileOutputStream.java:367)
at java.base/java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:125)
at java.base/java.io.BufferedOutputStream.implFlush(BufferedOutputStream.java:252)
at java.base/java.io.BufferedOutputStream.flush(BufferedOutputStream.java:240)
at com.azure.autorest.extension.base.jsonrpc.Connection.send(Connection.java:350)
... 7 more
Emitter "@azure-tools/typespec-java" crashed! This is a bug.
Please file an issue at https://github.com/Azure/autorest.java/issues

Error: JAR ended with code '1'.
at ChildProcess. (file:///C:/Users/daszanis/WORK/REPO/sdk-repos/sdk-repos/azure-sdk-for-java/sdk/healthdataaiservices/azure-health-deidentification/TempTypeSpecFiles/HealthDataAIServices.DeidServices/node_modules/@azure-tools/typespec-java/dist/src/emitter.js:123:37)
at ChildProcess.emit (node:events:517:28)
at ChildProcess._handle.onexit (node:internal/child_process:292:12)

--------------------------------------------------
Library Version 0.18.1
TypeSpec Compiler Version 0.58.0
Write-Error: C:\Users\daszanis\WORK\REPO\sdk-repos\azure-rest-api-specs\eng\scripts\TypeSpec-Generate-Sdk.ps1:92
Line |
92 | . $commonScript -TypeSpecProjectDirectory $TypeSpecProjectDirecto …
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| Failed to generate sdk project at
| C:\Users\daszanis\WORK\REPO\sdk-repos\sdk-repos\azure-sdk-for-java\sdk\healthdataaiservices\azure-health-deidentification
```

### Reproduction Steps

run `TypeSpec-Generate-Sdk.ps1` pointing to the `azure-sdk-for-java` repository

### Environment

Windows 11
Powershell Version 7

Start with eng/scripts/TypeSpec-Generate-Sdk.ps1 and the @azure-tools/typespec-java postprocessing path, then inspect the tsp config and customization/src/main/java/HealthDeidentificationSdkCustomization.java. Reproduce generation with and without customization in the azure-health-deidentification project and compare the failure around the closed pipe. Done means the SDK generates successfully with customization enabled.

Written by the indexing model from the issue text.