Fixed liniting error for validators' index.js files

refs f0242baf9f

- The index.js files in "input validators" are exposing an API and not doing anything else so these cases can be safely ignored
- Ideally we'd have a solution which would export all modules in the folder without having to add any more declarations, but that's for another time!

.eslintrc.js

@@ -37,6 +37,12 @@ module.exports = {
                 ]]
             }
         },
+        {
+            files: 'core/server/api/**/utils/validators/**/index.js',
+            rules: {
+                'max-lines': ['off']
+            }
+        },
         /**
          * @TODO: enable these soon
          */