feat(authenticator): Allow retry if fetchAuthSession fails

[mattcreaser]

• PR conforms to Pull Request guidelines.

Issue #, if available:
#203

Description of changes:
If the initial fetchAuthSession fails during Authenticator startup, the resulting error will allow retry. See screenshot below.

How did you test these changes?
Produced failure and verified behaviour.

Documentation update required?

• No
• Yes (Please include a PR link for the documentation update)

General Checklist

• Added Unit Tests
• Added Integration Tests
• Security oriented best practices and standards are followed (e.g. using input sanitization, principle of least privilege, etc)
• Ensure commit message has the appropriate scope (e.g fix(liveness): message, fix(authenticator): message, fix(all): message)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[mattcreaser]

We need retry for getCurrentUser failure as well.

[codecov]

Codecov Report

❌ Patch coverage is 34.09091% with 29 lines in your changes missing coverage. Please review.
✅ Project coverage is 32.62%. Comparing base (c60267d) to head (a30d4e5).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #210      +/-   ##
==========================================
+ Coverage   32.59%   32.62%   +0.02%     
==========================================
  Files         100      100              
  Lines        4608     4632      +24     
  Branches      583      585       +2     
==========================================
+ Hits         1502     1511       +9     
- Misses       2950     2964      +14     
- Partials      156      157       +1     

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