Add more rules to validate SDL

Author: IvanGoncharov

src/validation/specifiedRules.js

@@ -128,4 +128,6 @@ export const specifiedSDLRules: $ReadOnlyArray<SDLValidationRule> = [
   LoneSchemaDefinition,
   KnownDirectives,
   UniqueDirectivesPerLocation,
+  UniqueArgumentNames,
+  UniqueInputFieldNames,
 ];