docs: update cli eslint plugin configuration (#5579) [ci skip]

* docs: update cli eslint plugin configuration

* docs: sync cli-plugin-eslint README from core-plugins

* docs: update eslint plugin README

Author: jeneser

docs/core-plugins/eslint.md

@@ -23,7 +23,11 @@
 
 ## Configuration
 
-ESLint can be configured via `.eslintrc` or the `eslintConfig` field in `package.json`.
+ESLint can be configured via `.eslintrc` or the `eslintConfig` field in `package.json`. See the [ESLint configuration docs](https://eslint.org/docs/user-guide/configuring) for more detail.
+
+::: tip
+The following option is under the section of [`vue.config.js`](https://cli.vuejs.org/config/#vue-config-js). It is respected only when `@vue/cli-plugin-eslint` is installed.
+:::
 
 Lint-on-save during development with `eslint-loader` is enabled by default. It can be disabled with the `lintOnSave` option in `vue.config.js`:
 

packages/@vue/cli-plugin-eslint/README.md

@@ -23,7 +23,11 @@
 
 ## Configuration
 
-ESLint can be configured via `.eslintrc` or the `eslintConfig` field in `package.json`.
+ESLint can be configured via `.eslintrc` or the `eslintConfig` field in `package.json`. See the [ESLint configuration docs](https://eslint.org/docs/user-guide/configuring) for more detail.
+
+::: tip
+The following option is under the section of [`vue.config.js`](https://cli.vuejs.org/config/#vue-config-js). It is respected only when `@vue/cli-plugin-eslint` is installed.
+:::
 
 Lint-on-save during development with `eslint-loader` is enabled by default. It can be disabled with the `lintOnSave` option in `vue.config.js`: