[ESLint] replace .forEach with for..of

[dimaMachina]

A "for-of" loop is faster, as it doesn't need to execute the body function for each iteration (it's just a scope). This especially matters if the loop body is complex. sindresorhus/eslint-plugin-unicorn#1522 (comment)

also, GitHub has its own rule that does the same that unicorn plugin https://github.com/github/eslint-plugin-github/blob/main/docs/rules/array-foreach.md

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[changeset-bot]

🦋 Changeset detected

Latest commit: f0a1f95

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

This PR includes changesets to release 12 packages

Name	Type
codemirror-graphql	Patch
graphiql	Patch
@graphiql/react	Patch
@graphiql/toolkit	Patch
graphql-language-service	Patch
graphql-language-service-server	Patch
monaco-graphql	Patch
vscode-graphql-execution	Patch
@graphiql/plugin-explorer	Patch
cm6-graphql	Patch
graphql-language-service-cli	Patch
vscode-graphql	Patch

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