Add support for Reference Fix Commits improver

[ziadhany]

Issue:

• Create an improver that takes Patch with the advisories associated and tries to create valid PackageCommitPatches #2151

[ziadhany]

Pipeline Logs:

Importing data using collect_ref_fix_commits_v2
INFO 2026-02-20 02:47:26.911086 UTC Pipeline [CollectReferencesFixCommitsPipeline] starting
INFO 2026-02-20 02:47:26.911195 UTC Step [collect_and_store_fix_commits] starting
INFO 2026-02-20 02:47:32.898885 UTC Progress: 10% (2406/24056) ETA: 48 seconds
INFO 2026-02-20 02:47:38.421519 UTC Progress: 20% (4812/24056) ETA: 43 seconds
INFO 2026-02-20 02:47:44.849457 UTC Progress: 30% (7217/24056) ETA: 40 seconds
INFO 2026-02-20 02:47:52.147018 UTC Progress: 40% (9623/24056) ETA: 37 seconds
INFO 2026-02-20 02:47:59.019974 UTC Progress: 50% (12028/24056) ETA: 31 seconds
INFO 2026-02-20 02:48:05.477271 UTC Progress: 60% (14434/24056) ETA: 25 seconds
INFO 2026-02-20 02:48:13.080064 UTC Progress: 70% (16840/24056) ETA: 20 seconds
INFO 2026-02-20 02:48:20.902726 UTC Progress: 80% (19245/24056) ETA: 13 seconds
INFO 2026-02-20 02:48:27.613468 UTC Progress: 90% (21651/24056) ETA: 7 seconds
INFO 2026-02-20 02:48:30.112166 UTC Progress: 100% (24056/24056)
INFO 2026-02-20 02:48:30.112323 UTC Step [collect_and_store_fix_commits] completed in 63 seconds (1.1 minutes)
INFO 2026-02-20 02:48:30.112373 UTC Pipeline completed in 63 seconds (1.1 minutes)

Process finished with exit code 0

from vulnerabilities.models import PackageCommitPatch
PackageCommitPatch.objects.count()
Out[1]: 16986