[GitHub Actions] - Updates in Build Playground Backend to runs-on Self-hosted runners

[dannymartinm]

As part of the issue 21106, @elink21 and I have implemented the self-hosted runners for the Ubuntu and Windows operating systems.

Please see the Approved Pull Request (PR#22703) for reference.

In this PR you will find the following changes:

• Updates in workflow Build Playground Backend to runs-on self-hosted runners
  • Ubuntu

PR#16511 : Previous PR for reference.
BEAM-12812: Original Jira may contain additional context.

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