test(e2e): align object-lock overwrite tests with AWS new-version semantics
PR #3179 made put-like writes (PUT, CopyObject, multipart create/complete)
on versioned object-lock buckets create a new version instead of being
blocked by the current version's legal hold or COMPLIANCE retention, which
is the correct AWS behavior. Six e2e assertions in object_lock_test.rs
still encoded the old blocking semantics and, because e2e_test is excluded
from the CI test run, stayed red unnoticed since 2026-06-03.
Verified against a real server built from current main: all six failed at
their "should be blocked" assertions. Rewritten to assert the AWS
contract: the write succeeds with a distinct new version id, the new
content is current, the protected version keeps its content and lock
metadata, and version-targeted deletion of the protected version stays
blocked (for COMPLIANCE even with bypass_governance). Full object_lock
module is green again (33/33).
Zhengchao An