fix babel config for webpack build

[acao]

We had a very strange babel-loader failure in a PR today, which appears to be caused by some kind of regression in an upstream babel dependency. Perhaps should consider pinning dev dependencies. When we move to vite as proposed #2371, we will be removing babel

[changeset-bot]

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Latest commit: 382d520

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[github-actions]

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[codecov]

Codecov Report

Merging #2383 (382d520) into main (2d91916) will decrease coverage by 0.98%.
The diff coverage is 73.73%.

@@            Coverage Diff             @@
##             main    #2383      +/-   ##
==========================================
- Coverage   65.70%   64.72%   -0.99%     
==========================================
  Files          85       81       -4     
  Lines        5106     5324     +218     
  Branches     1631     1718      +87     
==========================================
+ Hits         3355     3446      +91     
- Misses       1747     1874     +127     
  Partials        4        4              

Impacted Files	Coverage Δ
packages/codemirror-graphql/src/hint.ts	94.73% <ø> (ø)
packages/codemirror-graphql/src/lint.ts	100.00% <ø> (ø)
packages/codemirror-graphql/src/results/mode.ts	47.05% <ø> (ø)
...kages/codemirror-graphql/src/utils/forEachState.ts	100.00% <ø> (ø)
packages/codemirror-graphql/src/utils/hintList.ts	95.65% <ø> (ø)
...ackages/codemirror-graphql/src/utils/info-addon.ts	1.02% <ø> (ø)
...ckages/codemirror-graphql/src/utils/mode-indent.ts	0.00% <0.00%> (ø)
packages/codemirror-graphql/src/variables/hint.ts	89.70% <ø> (ø)
packages/codemirror-graphql/src/variables/mode.ts	79.48% <ø> (ø)
packages/graphiql/src/utility/fillLeafs.ts	5.33% <ø> (ø)
... and 76 more

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