style: improve scrollbar styling on the query editor

[TPXP]

This changes makes scrollbars in the graphiql editor transparent, so that they look better integrated in the interface

Before	After

Scrollbars are transparent, so they look nice in light mode as well

I tested this on MacOS in Chrome, Firefox and Safari

Inspired by https://github.com/codemirror/codemirror5/pull/6882 as well

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 0926501c820b070b9d7e921bfa7f0430b52a18dc

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

This PR includes changesets to release 4 packages

Name	Type
@graphiql/react	Patch
graphiql	Patch
@graphiql/plugin-code-exporter	Patch
@graphiql/plugin-explorer	Patch

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[linux-foundation-easycla[bot]]

The committers listed above are authorized under a signed CLA.

• :white_check_mark: login: TPXP / name: Thomas P. (0926501c820b070b9d7e921bfa7f0430b52a18dc)

[acao]

@TPXP beautiful, thank you!