fix(implements-on-classes): had failed to check for tag itself; added test

Author: brettz9

src/rules/implementsOnClasses.js

@@ -14,7 +14,9 @@ export default iterateJsdoc(({
     return;
   }
 
-  report('@implements used on a non-constructor function');
+  if (utils.hasTag('implements')) {
+    report('@implements used on a non-constructor function');
+  }
 }, {
   meta: {
     type: 'suggestion'

test/rules/assertions/implementsOnClasses.js

@@ -53,6 +53,16 @@ export default {
         }
       }
       `
+    },
+    {
+      code: `
+      /**
+       *
+       */
+      function quux () {
+
+      }
+      `
     }
   ]
 };