Use .eslintrc.js in examples

.eslintrc is deprecated since ESLint v7

Author: Maximization

README.md

@@ -20,7 +20,7 @@ Install this package and ESLint:
 npm install --save-dev eslint eslint-config-async
 ```
 
-In your `.eslintrc` configuration file:
+In your `.eslintrc.js` configuration file:
 
 ```js
 module.exports = {
@@ -37,7 +37,7 @@ Install this package and its peer dependencies:
 npm install --save-dev eslint eslint-config-async eslint-plugin-node
 ```
 
-In your `.eslintrc` configuration file:
+In your `.eslintrc.js` configuration file:
 
 ```js
 module.exports = {
@@ -58,7 +58,7 @@ Install this package and its peer dependencies:
 npm install --save-dev eslint eslint-config-async eslint-plugin-node typescript @typescript-eslint/parser @typescript-eslint/eslint-plugin
 ```
 
-In your `.eslintrc` configuration file:
+In your `.eslintrc.js` configuration file:
 
 ```js
 module.exports = {
@@ -127,4 +127,4 @@ module.exports = {
 -   "@typescript-eslint/promise-function-async": "error",
   }
 }
-```
+```