Build: remove DEDUPLICATE_BUILDS feature

[humitos]

With the introduction of CANCEL_OLD_BUILDS we are moving away from the DEDUPLICATE_BUILDS feature since these scenario is managed in a better way by the new feature.

Closes #7306
Related #9549

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📚 Documentation previews 📚

• User's documentation (docs): https://docs--9591.org.readthedocs.build/en/9591/

• Developer's documentation (dev): https://dev--9591.org.readthedocs.build/en/9591/

[humitos]

@stsewd I'm confused. Didn't we already fix this? 🤔

WARNINGS:
?: (urls.W001) Your URL pattern '^api/v2/search/$' uses include with a route ending with a '$'. Remove the dollar from the route to avoid problems including URLs.

"checks" are failing because of this.

[stsewd]

@stsewd I'm confused. Didn't we already fix this? thinking

WARNINGS:
?: (urls.W001) Your URL pattern '^api/v2/search/$' uses include with a route ending with a '$'. Remove the dollar from the route to avoid problems including URLs.

"checks" are failing because of this.

Haven't fixed it, but that's a warning (the url still works), the error you get is because you have pending migrations

Migrations for 'builds':
readthedocs/builds/migrations/0045_alter_build_status.py
- Alter field status on buil

[humitos]

@stsewd thanks! I update the PR with the missing migration. I think it's ready to merge.