fix(webpack): fix double export

[gregberge]

Closes #645

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[codecov]

Codecov Report

Merging #648 (abdc914) into main (7b5aa0f) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #648   +/-   ##
=======================================
  Coverage   92.43%   92.43%           
=======================================
  Files          32       32           
  Lines         727      727           
  Branches      235      239    +4     
=======================================
  Hits          672      672           
  Misses         53       53           
  Partials        2        2           

Impacted Files	Coverage Δ
packages/webpack/src/index.ts	84.84% <100.00%> (ø)

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