### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

copyObject and putObject (and perhaps other requests) requests are accepted and do not return an error when an SSE KMS key is specified. 

### Expected Behavior

The error which should be returned is KMS.NotFoundException.

### How are you starting LocalStack?

Custom (please describe below)

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

    Localstack testcontainers 

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

   Call copyObject/putObject via latest version using AWS SDK V2 and specific a ssekmsKeyId.

```java
final var copyObjectRequestBuilder =
        CopyObjectRequest.builder()
            .serverSideEncryption(ServerSideEncryption.AWS_KMS)
            .ssekmsKeyId("NON-EXISTENT KMS KEY")
            .sourceBucket(sourceBucketName)
            .sourceKey(sourceKey)
            .destinationBucket(destinationBucket)
            .destinationKey(destinationKey);
final var copyObjectResponse = sourceRegionS3Client.copyObject(copyObjectRequest); // Error should be thrown here but localstack does not return an error
```

### Environment

```markdown
- OS: MacOS 13.0
- LocalStack: Latest (v1.2.0)
```


### Anything else?

_No response_
self, context: RequestContext, bucket: BucketName, body: IO[Body] = None
    ) -> PostResponse:
        
        
        
        validate_post_policy(context.request.form)
        
        
        
        try:
            response: PostResponse = call_moto(context=context)
        except ServiceException as e:
            if e.status_code == 303:
                
                response = PostResponse(StatusCode=e.status_code)
            else:
                raise e
        key_name = context.request.form.get("key")
        if "${filename}" in key_name:
            key_name = key_name.replace("${filename}", context.request.files["file"].filename)
        moto_backend = get_moto_s3_backend(context)
        key = get_key_from_moto_bucket(
            get_bucket_from_moto(moto_backend, bucket=bucket), key=key_name
        )