fix(babel): fixed esm detection in node_modules

[Anber]

Motivation

Some files in node_modules weren't detected as ESM. See #1242

Summary

The regular expression used to detect the keywords export or import contained an error that resulted in a false negative for ESM files that did not have any imports.

[changeset-bot]

🦋 Changeset detected

Latest commit: b5031e9

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 15 packages

Name	Type
@linaria/babel-preset	Patch
@linaria/cli	Patch
@linaria/esbuild	Patch
linaria	Patch
@linaria/rollup	Patch
@linaria/stylelint	Patch
@linaria/testkit	Patch
@linaria/vite	Patch
@linaria/webpack4-loader	Patch
@linaria/webpack5-loader	Patch
esbuild-example	Patch
rollup-example	Patch
vite-example	Patch
vpssr-linaria-solid-example	Patch
@linaria/webpack-loader	Patch

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[nstepien]

I wonder if this is safe, the import or export words could be in a string in the code for example.
Using babel's parser to get the AST may be safer, no?

[Anber]

False positive causes just a bit more work, whereas false negative causes errors during the evaluation stage. So, false positive cases are not a big problem.
AST will be safer but more expensive cause we need to parse each file. Theoretically, we can parse only files that contain import or export and then reuse parsed AST, but it requires more complicated rules definition API.