minor #874 Update Stimulus test to use an ES syntax (tgalopin)

This PR was merged into the main branch.

Discussion
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Update Stimulus test to use an ES syntax

Following the proposal of symfony/stimulus-bridge#1, this PR checks ES module syntax work as expected.

Commits
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d6eb263 Update Stimulus test to use an ES syntax

fixtures/stimulus/controllers/index.js

@@ -1,3 +1,3 @@
-module.exports = {
+export default {
     '@symfony/mock-module/mock': import(/* webpackMode: "eager" */ '@symfony/mock-module/dist/controller'),
 };