Rollup merge of #97530 - GuillaumeGomez:more-eslint-checks, r=jsha

Add more eslint checks

Here is a new batch of eslint checks:

 * [no-const-assign](https://eslint.org/docs/rules/no-const-assign)
 * [no-debugger](https://eslint.org/docs/rules/no-debugger)
 * [no-dupe-args](https://eslint.org/docs/rules/no-dupe-args)
 * [no-duple-else-if](https://eslint.org/docs/rules/no-dupe-else-if)
 * [no-dupe-keys](https://eslint.org/docs/rules/no-dupe-keys)
 * [no-duplicate-case](https://eslint.org/docs/rules/no-duplicate-case)
 * [no-ex-assign](https://eslint.org/docs/rules/no-ex-assign)

r? ``@notriddle``

Author: compiler-errors

src/librustdoc/html/static/.eslintrc.js

@@ -63,5 +63,12 @@ module.exports = {
             }
         ],
         "eqeqeq": "error",
+        "no-const-assign": "error",
+        "no-debugger": "error",
+        "no-dupe-args": "error",
+        "no-dupe-else-if": "error",
+        "no-dupe-keys": "error",
+        "no-duplicate-case": "error",
+        "no-ex-assign": "error",
     }
 };