Revert "docs: add fast-eslint-8 to atom integrations (userguide) (esl…

…int#15695)"

This reverts commit 017a9c9.

docs/user-guide/integrations.md

@@ -14,9 +14,7 @@
 * TextMate 2:
     * [eslint.tmbundle](https://github.com/ryanfitzer/eslint.tmbundle)
     * [javascript-eslint.tmbundle](https://github.com/natesilva/javascript-eslint.tmbundle)
-* Atom:
-    * [linter-eslint](https://atom.io/packages/linter-eslint)
-    * [fast-eslint-8](https://atom.io/packages/fast-eslint-8)
+* Atom: [linter-eslint](https://atom.io/packages/linter-eslint)
 * IntelliJ IDEA, WebStorm, PhpStorm, PyCharm, RubyMine, and other JetBrains IDEs: [How to use ESLint](https://www.jetbrains.com/help/webstorm/eslint.html)
 * Visual Studio Code: [ESLint Extension](https://marketplace.visualstudio.com/items?itemName=dbaeumer.vscode-eslint)
 * Brackets: Included and [Brackets ESLint](https://github.com/brackets-userland/brackets-eslint)