test: Expand Test Coverage

[evansims]

Description

This PR updates the unit tests to expand coverage.

Checklist

• [x] My code follows the contributing guidelines of this repo
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass with my changes
• [x] I have read the Auth0 general contribution guidelines
• [x] I have read the Auth0 code of conduct

[github-actions[bot]]

👋 Thanks for contributing! Please be patient while a maintainer reviews your PR. In the meantime, please make sure you've read our contributing guide.

[evansims]

Please disregard the two failing 'Contributors' workflow statuses, that's something I'm working on separately. Fixed 😁

[codecov-commenter]

Codecov Report

Base: 95.03% // Head: 95.03% // No change to project coverage :thumbsup:

Coverage data is based on head (336bf7d) compared to base (b88e79b). Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #697 +/- ## ========================================= Coverage 95.03% 95.03% Complexity 1252 1252 ========================================= Files 65 65 Lines 4411 4411 ========================================= Hits 4192 4192 Misses 219 219 ``` | [Impacted Files](https://codecov.io/gh/auth0/auth0-PHP/pull/697?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0) | Coverage Δ | | |---|---|---| | [src/Configuration/SdkConfiguration.php](https://codecov.io/gh/auth0/auth0-PHP/pull/697?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0#diff-c3JjL0NvbmZpZ3VyYXRpb24vU2RrQ29uZmlndXJhdGlvbi5waHA=) | `72.10% <100.00%> (ø)` | | | [src/Configuration/SdkState.php](https://codecov.io/gh/auth0/auth0-PHP/pull/697?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0#diff-c3JjL0NvbmZpZ3VyYXRpb24vU2RrU3RhdGUucGhw) | `79.12% <100.00%> (ø)` | | Help us with your feedback. Take ten seconds to tell us [how you rate us](https://about.codecov.io/nps?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0). Have a feature suggestion? [Share it here.](https://app.codecov.io/gh/feedback/?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0)

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