(codebuild): removing vpc from codebuild project will not actually remove the vpc configuration

### Describe the bug

If you build a CodeBuild Project first with a vpc and deploy, then remove the vpc and perform the second deploy, the related IAM permission would be removed but the vpc remains in the CodeBuild Project's configuration.

Below is a simple example that I can use to reproduce the problem

```
export class MyStack extends Stack {
constructor(scope: Construct, id: string, props: StackProps = {}) {
super(scope, id, props);

const vpc = ec2.Vpc.fromLookup(this, "Vpc", {
vpcId: "vpc-12345678", // any valid vpc id in the target account
});

new codebuild.Project(this, "Project", {
// vpc,
buildSpec: codebuild.BuildSpec.fromObject({
version: "0.2",
env: {},
phases: {
build: {
commands: 'echo "Hello World!"',
},
},
}),
});
}
}
```

This is problematic especially with pipeline, because the pipeline would fail because it can't perform `ec2:DescribeNetworkInterfaces` on the vpc and the project fails during Queue time.

### Expected Behavior

The VPC configuration be cleared from the CodeBuild Project.

### Current Behavior

The VPC configuration remains in the CodeBuild Project according to console and cli.

### Reproduction Steps

First deploy this

```
export class MyStack extends Stack {
constructor(scope: Construct, id: string, props: StackProps = {}) {
super(scope, id, props);

const vpc = ec2.Vpc.fromLookup(this, "Vpc", {
vpcId: "vpc-12345678", // any valid vpc id in the target account
});

new codebuild.Project(this, "Project", {
vpc,
buildSpec: codebuild.BuildSpec.fromObject({
version: "0.2",
env: {},
phases: {
build: {
commands: 'echo "Hello World!"',
},
},
}),
});
}
}
```

then deploy this

```
export class MyStack extends Stack {
constructor(scope: Construct, id: string, props: StackProps = {}) {
super(scope, id, props);

ec2.Vpc.fromLookup(this, "Vpc", {
vpcId: "vpc-12345678", // any valid vpc id in the target account
});

new codebuild.Project(this, "Project", {
// vpc,
buildSpec: codebuild.BuildSpec.fromObject({
version: "0.2",
env: {},
phases: {
build: {
commands: 'echo "Hello World!"',
},
},
}),
});
}
}
```

The second deploy would remove the Project role's ability to perform various ec2 actions, including `ec2:DescribeNetworkInterfaces`. But the vpc configuration remains in the Project (according to console as well as aws cli)

### Possible Solution

_No response_

### Additional Information/Context

_No response_

### CDK CLI Version

2.50.0

### Framework Version

_No response_

### Node.js Version

v18.6.0

### OS

MacOS

### Language

Typescript

### Language Version

_No response_

### Other information

_No response_

Reproduce the issue by deploying the CodeBuild project first with a VPC and then without one, using the TypeScript examples in the report. Inspect the generated project update and verify the AWS console or CLI; done means the VPC configuration and related permissions are both cleared after the second deployment.

Written by the indexing model from the issue text.