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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

When using java-aws-sdk `CreateFunctionRequest` and `UpdateFunctionCodeRequest` with `publish` flag set to `true` should publish new version of lambda function. When I tried such operations against localstack container in version `localstack/localstack:0.11.2` those operations didn't publish new function version.

## Expected behavior

`CreateFunctionResponse` nad `UpdateFunctionCodeResponse` when `publish` flag is set to `true` will return under `version` field new version of changed AWS lambda function.

## Actual behavior

Even flag `publish` is set to `true`, above operations responses return in version `$LATEST` value what indicate that operation didn't produce new function version

# Steps to reproduce
- check available versions of given function
- create function or update existing with `publish` flag set to `true`
```
CreateFunctionRequest.builder
      .functionName(functionName)
      .runtime(runtimeName)
      .handler(handlerName)
      .layers(functionLayers)
      .role(lambdaExecutionRole)
      .tags(cdsLambdaTags)
      .memorySize(memorySize)
      .code(functionCode)
      .publish(true)
      .build
//or
UpdateFunctionCodeRequest.builder()
      .functionName(functionName)
      .zipFile(functionCode.zipFile())
      .publish(true)
      .build()
```
- check available versions of given function

## Command used to start LocalStack

Used testcontainers java localstack library.

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

```
CreateFunctionRequest.builder
      .functionName(functionName)
      .runtime(runtimeName)
      .handler(handlerName)
      .layers(functionLayers)
      .role(lambdaExecutionRole)
      .tags(cdsLambdaTags)
      .memorySize(memorySize)
      .code(functionCode)
      .publish(true)
      .build
//or
UpdateFunctionCodeRequest.builder()
      .functionName(functionName)
      .zipFile(functionCode.zipFile())
      .publish(true)
      .build()
```
try:
        ARN_TO_CODE_SIGNING_CONFIG.pop(arn)
    except KeyError:
        msg = 'The Lambda code signing configuration %s can not be found.' % (arn)
        return error_response(msg, 404, error_type='ResourceNotFoundException')
    return Response('', status=204)
@app.route('/2020-04-22/code-signing-configs/<arn>', methods=['PUT'])
def update_code_signing_config(arn):
    try:
        code_signing_obj = ARN_TO_CODE_SIGNING_CONFIG[arn]
    except KeyError:
        msg = 'The Lambda code signing configuration %s can not be found.' % (arn)
        return error_response(msg, 404, error_type='ResourceNotFoundException')
    data = json.loads(request.data)
    is_updated = False
    if data.get('Description'):
        code_signing_obj.description = data['Description']