fix: self conversion

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 60.00000% with 4 lines in your changes missing coverage. Please review.

Project coverage is 90.90%. Comparing base (549530a) to head (293044a). Report is 1 commits behind head on main.

Files	Patch %	Lines
src/unxt/_unxt/quantity/compat.py	60.00%	4 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #163 +/- ## ========================================== - Coverage 91.10% 90.90% -0.20% ========================================== Files 32 32 Lines 1574 1584 +10 ========================================== + Hits 1434 1440 +6 - Misses 140 144 +4 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.