Make eslint-plugin-jest an optional peerDependency (#9670)

Author: MichaelDeBoey

packages/eslint-config-react-app/README.md

@@ -19,7 +19,7 @@ If you want to use this ESLint configuration in a project not built with Create
 First, install this package, ESLint and the necessary plugins.
 
 ```sh
-npm install --save-dev eslint-config-react-app @typescript-eslint/eslint-plugin@^4.0.0 @typescript-eslint/parser@^4.0.0 babel-eslint@^10.0.0 eslint@^7.5.0 eslint-plugin-flowtype@^5.2.0 eslint-plugin-import@^2.22.0 eslint-plugin-jest@^24.0.0 eslint-plugin-jsx-a11y@^6.3.1 eslint-plugin-react@^7.20.3 eslint-plugin-react-hooks@^4.0.8
+npm install --save-dev eslint-config-react-app @typescript-eslint/eslint-plugin@^4.0.0 @typescript-eslint/parser@^4.0.0 babel-eslint@^10.0.0 eslint@^7.5.0 eslint-plugin-flowtype@^5.2.0 eslint-plugin-import@^2.22.0 eslint-plugin-jsx-a11y@^6.3.1 eslint-plugin-react@^7.20.3 eslint-plugin-react-hooks@^4.0.8
 ```
 
 Then create a file named `.eslintrc.json` with following contents in the root folder of your project:

packages/eslint-config-react-app/package.json

@@ -28,6 +28,11 @@
     "eslint-plugin-react": "^7.20.3",
     "eslint-plugin-react-hooks": "^4.0.8"
   },
+  "peerDependenciesMeta": {
+    "eslint-plugin-jest": {
+      "optional": true
+    }
+  },
   "dependencies": {
     "confusing-browser-globals": "^1.0.9"
   },