fix(brew): improve handling of single os

[caarlos0]

• refactors brew template into separated files using embed.FS
• moves the macos and linux packages to different template files
• includes and indent those accordingly to which OSes are supported

closes #4561

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

❗ No coverage uploaded for pull request base (main@116a034). Click here to learn what that means.
Report is 1 commits behind head on main.

Files	Patch %	Lines
internal/pipe/brew/brew.go	76.92%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4562   +/-   ##
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  Coverage        ?   83.75%           
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  Files           ?      135           
  Lines           ?    12938           
  Branches        ?        0           
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  Hits            ?    10836           
  Misses          ?     1673           
  Partials        ?      429           

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