chore: migrate to node.js native test runner

Author: SethFalco

.mocharc.js

@@ -24,7 +24,6 @@ export default [
         "sourceType": "module",
         "globals": {
           "node": true,
-          "mocha": true,
           "es2019": true
         }
       }

eslint.config.mjs

@@ -79,4 +79,4 @@ fi
   }
 }
 
-module.exports = Completion;
+module.exports = Completion;