[main] (deps): Bump dotnet/arcade/.github/workflows/backport-base.yml (#69228)

Bumps [dotnet/arcade/.github/workflows/backport-base.yml](https://github.com/dotnet/arcade) from 96ac7c3d84e2b772f0b3a125e17482394d67a61a to bb31c98899c1070a3b82333ead0a8663fc2c0c12.
- [Commits](https://github.com/dotnet/arcade/compare/96ac7c3d84e2b772f0b3a125e17482394d67a61a...bb31c98899c1070a3b82333ead0a8663fc2c0c12)

---
updated-dependencies:
- dependency-name: dotnet/arcade/.github/workflows/backport-base.yml
  dependency-version: bb31c98899c1070a3b82333ead0a8663fc2c0c12
  dependency-type: direct:production
...

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