rgw: Add pytest-based RGW dedup full feature automation coverage.

[viduship]

Complete dedup test automation covering sanity, feature, compression, bug regression, enhancement, restart, concurrent, edge-case, and infrastructure failure scenarios. Includes IBMCEPH-17201 LC regression tests for deduped >4MB objects.

Files added/modified:

• test_dedup_pytest.py : 58 pytest tests (main suite)
• test_dedup_scale_pytest.py: 8 scale/perf tests (separate suite)
• test_dedup.py : Non-pytest dedup test module
• conftest.py : Pytest fixtures (s3_client, bucket, etc.)
• reusables/dedup.py : Shared helpers (upload, dedup, verify)
• run_dedup_pytest.py : cephci-to-pytest wrapper
• pytest.ini : Marker definitions and logging config
• upload_dedup_1b_v1.py : 1B object upload script for scale testing
• configs/test_dedup_*.yaml : 49 per-test YAML configs

all passed logs http://magna002.ceph.redhat.com/cephci-jenkins/cephci-run-AV5T5S

[mkasturi18]

lgtm