chore: More test coverage on supabase_flutter

[dshukertjr]

What kind of change does this PR introduce?

Bug fix, feature, docs update, ...

What is the current behavior?

Please link any relevant issues here.

What is the new behavior?

Feel free to include screenshots if it includes visual changes.

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 15676617889

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 11 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.9%) to 81.596%

---

Files with Coverage Reduction	New Missed Lines	%
packages/supabase_flutter/lib/src/supabase.dart	11	81.33%

Totals
Change from base Build 15578916758:	0.9%
Covered Lines:	3139
Relevant Lines:	3847

---

💛 - Coveralls