Increase token expiration and retry until compatible token

[jander-msft]

Summary

• Increase the token expiration for Helix runs. The test job allows Helix up to 2 hours since it can take some time to wait in the Helix queues before tests are run. Don't want the token to expire before the tests get a chance to run.
• Update the get-delegation-sas yaml to retry getting a token if it contains a forward slash. Tokens with forward slashes seem to trip up Helix and cause it to not download the correlation payload. Similar workarounds have been employed elsewhere: https://github.com/dotnet/aspnetcore/blob/release/6.0/eng/common/templates-official/steps/get-delegation-sas.yml#L34

Validation build: https://dev.azure.com/dnceng/internal/_build/results?buildId=2528027&view=results

Release Notes Entry

[jander-msft]

/backport to main

[jander-msft]

/backport to release/8.0

[github-actions]

Started backporting to main: https://github.com/dotnet/dotnet-monitor/actions/runs/10641479158

[github-actions]

Started backporting to release/8.0: https://github.com/dotnet/dotnet-monitor/actions/runs/10641479839

[jander-msft]

/backport to release/8.0

[github-actions]

Started backporting to release/8.0: https://github.com/dotnet/dotnet-monitor/actions/runs/11186596050