fix(cli): fix index generation

[gregberge]

Fixes #433

Summary

Test plan

[vercel]

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[codecov]

Codecov Report

Merging #443 into master will increase coverage by 0.69%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #443      +/-   ##
==========================================
+ Coverage   86.53%   87.22%   +0.69%     
==========================================
  Files          31       31              
  Lines         557      595      +38     
  Branches      153      169      +16     
==========================================
+ Hits          482      519      +37     
- Misses         60       61       +1     
  Partials       15       15              

Impacted Files	Coverage Δ
...s/babel-plugin-transform-svg-component/src/util.js	96.11% <0.00%> (+0.73%)	⬆️

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