A bucket GET with both the uploads and uploadId query parameters was
routed to ListMultipartUploads and answered with the upload listing.
S3 rejects the combination with 400 InvalidArgument, "Conflicting query
string parameters: uploadId, uploads".
Add an error route for the combination ahead of ListMultipartUploads,
the way the object level '?uploads' request is rejected, and enable
the REST test that covers it.
Fixes#2155
A region specific endpoint requires CreateBucket to name that same region
in `LocationConstraint`. The gateway reported a mismatch as
`InvalidLocationConstraint`, which AWS reserves for a constraint that is
not a valid location at all, and accepted a request that omitted the
constraint entirely.
Keep `InvalidLocationConstraint` for the global `us-east-1` endpoint,
which takes no constraint, and return
`IllegalLocationConstraintException` when a region specific endpoint gets
a constraint naming another region, or none.
Fixes#2246