Refactor Timestamp to avoid mistakes

[miqrogroove]

Fixes #4923

By implementing Carbon helper methods, we avoid some of the copypasta found in v2.1.0.

[codecov[bot]]

Codecov Report

Attention: 13 lines in your changes are missing coverage. Please review.

Comparison is base (a609a18) 32.13% compared to head (993f36f) 32.15%.

Files	Patch %	Lines
app/Timestamp.php	0.00%	13 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #4924 +/- ## ============================================ + Coverage 32.13% 32.15% +0.01% + Complexity 11394 11382 -12 ============================================ Files 1171 1171 Lines 48019 47995 -24 ============================================ Hits 15431 15431 + Misses 32588 32564 -24 ```

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

[fisharebest]

Thanks!

[miqrogroove]

@fisharebest Thanks for the commit! I will work on refreshing the other Timestamp patch for the bigger bugs.