feat: make each changelog commit a list item

[caarlos0]

Made a few changes here:

• commits are now list items (someone asked this, I always wanted to do this, don't see why not as it looks better)
• refactor some code from feat: CHANGELOG categories #2670
  • compile each regex only once
  • rename method
  • check if regex is valid and error otherwise
    • also added a test for this

cc/ @dirien

---

example output:

## Changelog

### New Features

* 81c53073a4d4b638cec836ccb6cee78052695b3a: feat(ci): add cosign public key to releases (#2636) (@erkanzileli)
* a94e28b77c40d0ff483f618e77d2defdc637e54f: feat(deps): bump golang from 1.17.2-alpine to 1.17.3-alpine (#2632) (@dependabot[bot])

### Bug fixes

* 1e718d2db0a612fe79e25292889c9ca10a97e563: Revert "fix: armv7 on linux is usually armv7l" (@caarlos0)
* c958e4cc5e18073116881a7dd79355ca9197871a: fix: changelog is too long (#2661) (@dirien)

### Other work

* 048557efdb35d87f628ff1206ebff48b44229075: Merge remote-tracking branch 'origin/main' (@caarlos0)
* cf73ede93248e0de9a3a1cc6e5d12f03d4492b7d: refactor: improve changelog code (@caarlos0)

[codecov]

Codecov Report

Merging #2695 (2dcbc0a) into main (419b6fc) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2695      +/-   ##
==========================================
- Coverage   84.76%   84.76%   -0.01%     
==========================================
  Files         103      103              
  Lines        7883     7882       -1     
==========================================
- Hits         6682     6681       -1     
  Misses        985      985              
  Partials      216      216              

Impacted Files	Coverage Δ
internal/pipe/changelog/changelog.go	91.35% <100.00%> (-0.04%)	⬇️

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[wesleimp]

LGTM 👌🏼

[dirien]

I like it! Good changes! 👍🏻