feat: add input for the config repository

[flugg]

Fixes #130

This PR adds the possibility to the set a shared configuration as input.

[codecov]

Codecov Report

Merging #131 (ab266d9) into main (b1fea02) will decrease coverage by 0.40%.
The diff coverage is 80.00%.

@@             Coverage Diff             @@
##              main     #131      +/-   ##
===========================================
- Coverage   100.00%   99.59%   -0.41%     
===========================================
  Files           11       11              
  Lines          241      245       +4     
  Branches        79       82       +3     
===========================================
+ Hits           241      244       +3     
- Partials         0        1       +1     

Impacted Files	Coverage Δ
src/config.ts	95.83% <80.00%> (-4.17%)	⬇️

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