impl(auth): add retry to impersonated idtoken provider

[alvarowolfx]

Towards #3592

[alvarowolfx]

I don't know why the diff is looking weird here on Github. But I removed the test_impersonated_id_token_fail test as with retries, is not gonna hard fail in one call.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.83%. Comparing base (30e002e) to head (1eb1ad1).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4257   +/-   ##
=======================================
  Coverage   94.82%   94.83%           
=======================================
  Files         187      187           
  Lines        7147     7159   +12     
=======================================
+ Hits         6777     6789   +12     
  Misses        370      370           

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