[3.0.x] Refs #22463 -- Replaced JSHint with ESLint in contributing docs.

Backport of 7b4bd2a from master

docs/internals/contributing/writing-code/javascript.txt

@@ -20,9 +20,9 @@ Code style
   Different JavaScript files sometimes use a different code style. Please try to
   conform to the code style of each file.
 
-* Use the `JSHint`_ code linter to check your code for bugs and style errors.
-  JSHint will be run when you run the JavaScript tests. We also recommended
-  installing a JSHint plugin in your text editor.
+* Use the `ESLint`_ code linter to check your code for bugs and style errors.
+  ESLint will be run when you run the JavaScript tests. We also recommended
+  installing a ESLint plugin in your text editor.
 
 * Where possible, write code that will work even if the page structure is later
   changed with JavaScript. For instance, when binding a click handler, use
@@ -147,6 +147,6 @@ Then run the tests with:
 .. _Closure Compiler: https://developers.google.com/closure/compiler/
 .. _EditorConfig: https://editorconfig.org/
 .. _Java: https://www.java.com
-.. _jshint: https://jshint.com/
+.. _eslint: https://eslint.org/
 .. _node.js: https://nodejs.org/
 .. _qunit: https://qunitjs.com/