fix(svgo): support any SVGO config format

[gregberge]

Fixes #400

Summary

Test plan

[vercel]

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[codecov]

Codecov Report

Merging #412 into master will decrease coverage by 0.57%.
The diff coverage is 78.26%.

@@            Coverage Diff             @@
##           master     #412      +/-   ##
==========================================
- Coverage   85.55%   84.98%   -0.58%     
==========================================
  Files          30       31       +1     
  Lines         526      526              
  Branches      143      145       +2     
==========================================
- Hits          450      447       -3     
- Misses         63       64       +1     
- Partials       13       15       +2     

Impacted Files	Coverage Δ
packages/plugin-svgo/src/config.js	76.19% <76.19%> (ø)
packages/plugin-svgo/src/index.js	66.66% <100.00%> (-7.94%)	⬇️

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[kuoruan]

@gregberge Missing .svgorc.js