This PR also tries to simplify the approach taken in
object-locking implementation by preferential treatment
given towards full validation.
This in-turn has fixed couple of bugs related to
how policy should have been honored when ByPassGovernance
is provided.
Simplifies code a bit, but also duplicates code intentionally
for clarity due to complex nature of object locking
implementation.
AWS S3 doesn't enforce the URL in XMLNS, accordingly, removing the
URL in XMLNS for ObjectLegalHold.
This was found while testing https://github.com/minio/minio-go/pull/1226
