### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

The Complete Multipart Upload operation generates the **InternalError** error for non-existing uploads.

### Expected Behavior

The Complete Multipart Upload operation generates the **NoSuchUpload** error for non-existing uploads.

### How are you starting LocalStack?

With a `docker run` command

### Steps To Reproduce

    docker run -it --rm -p 4566:4566 localstack/localstack

    aws s3api create-bucket --bucket test --endpoint-url http://localhost:4566 --create-bucket-configuration LocationConstraint=us-west-2

    aws s3api complete-multipart-upload --bucket test --endpoint-url http://localhost:4566 --key test --upload-id test

### Environment

```markdown
- OS: Windows 11
- LocalStack: latest
```


### Anything else?

The Abort Multipart Upload operation works correctly in LocalStack.

The official documentation: https://docs.aws.amazon.com/AmazonS3/latest/API/API_CompleteMultipartUpload.html
Amazon S3 throws the correct **NoSuchUpload** error for both Abort and Complete operations.
AbortDate: Optional[AbortDate]
    AbortRuleId: Optional[AbortRuleId]
    Bucket: Optional[BucketName]
    Key: Optional[ObjectKey]
    UploadId: Optional[MultipartUploadId]
    PartNumberMarker: Optional[PartNumberMarker]
    NextPartNumberMarker: Optional[NextPartNumberMarker]
    MaxParts: Optional[MaxParts]
    IsTruncated: Optional[IsTruncated]
    Parts: Optional[Parts]
    Initiator: Optional[Initiator]
    Owner: Optional[Owner]
    StorageClass: Optional[StorageClass]
    RequestCharged: Optional[RequestCharged]
    ChecksumAlgorithm: Optional[ChecksumAlgorithm]
class ListPartsRequest(ServiceRequest):
    Bucket: BucketName
    Key: ObjectKey
    MaxParts: Optional[MaxParts]
    PartNumberMarker: Optional[PartNumberMarker]
    UploadId: MultipartUploadId
    RequestPayer: Optional[RequestPayer]
    ExpectedBucketOwner: Optional[AccountId]
    SSECustomerAlgorithm: Optional[SSECustomerAlgorithm]
    SSECustomerKey: Optional[SSECustomerKey]
    SSECustomerKeyMD5: Optional[SSECustomerKeyMD5]
class MetadataEntry(TypedDict, total=False):