Get Blob Metadata also returns full content of the Blob

### Which service(blob, file, queue, table) does this issue concern?
BLOB

### Which version of the Azurite was used?
3.9.0

### Where do you get Azurite? (npm, DockerHub, NuGet, Visual Studio Code Extension)
Dockerhub

### What's the Node.js version?
included

### What problem was encountered?
Get Blob Metadata : the REST reply does not only contain the MetaData, but it also contains the full content of the BLOB. Only the Meta Data should be transferred.

### Steps to reproduce the issue?
Create a container " my container"
create a Blob in this container "my blob"
write a stream of some data into "my blob"
set some meta data on "myBlob"

when you issue the GetBlobMetadata command

GET /devstoreaccount1/mycontainer/myblob?comp=metadata&timeout=30 HTTP/1.1

The reply contains headers and the Metadata, but "content-length" shows the length of the Blob content and the content of the blob is also transferred in the reply

This makes the Get Blob Metadata Querries slow for large Blobs

I used Telerik Fiddler Web debugger to look at the response.

### Have you found a mitigation/solution?
I use the list blob function with the name of the blob as prefix. This gives also the Metadata of the blob, but it does not send the whole content of the blob in the response.