Fix SignalR token retry for thrown 401 errors

[pradeep-ramola]

Jest: 2 test files passed, 26 tests passed
ESLint: touched test files passed
build:cjs: passed
build:esm: passed
git diff --check: passed

[dotnet-policy-service]

Thanks for your PR, @pradeep-ramola. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[pradeep-ramola]

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[gfoidl]

What's the difference to #67851?
Or why should this PR prefered over the other one?

[pradeep-ramola]

What's the difference to #67851? Or why should this PR prefered over the other one?

Thanks for pointing this out.

You're right that #67851 covers the same core issue and was opened earlier. The main difference is that this PR adds coverage through the LongPolling/SSE transport paths, while #67851 focuses the tests directly on AccessTokenHttpClient and also extracts the shared retry logic into a helper.

I don't think this PR needs to be preferred over #67851. If the maintainers prefer to move forward with #67851, I'm happy to close this as a duplicate. If the extra transport-level coverage here is useful, I can also keep this open only as reference or follow up separately with that coverage.