fix typo and clarify wording (#1342)

Author: jesseb34r

src/routes/solid-router/reference/data-apis/action.mdx

@@ -127,7 +127,7 @@ const submission = useSubmission(action, (input) => filter(input));
 ##  Revalidate cached functions
 
 ###  Revalidate all (default)
-By default all cached functions will be revalidated wether the action does not return or return a "normal" response.
+By default, all cached functions will be revalidated whether the action returns no response or a "normal" response.
 
 ```jsx