fix: fix flaky tests, cleanup code

[ilaborie]

No description provided.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.4%. Comparing base (c4ce0fa) to head (e3bb9c3).
Report is 4 commits behind head on main.

Additional details and impacted files

Files with missing lines	Coverage Δ
schema-registry-api/src/domain/schema/version.rs	93.5% <ø> (+4.6%)	⬆️

... and 18 files with indirect coverage changes

[ilaborie]

Issue with minimal version is reported here: TrueLayer/reqwest-middleware#204