Update filters.md (#1454)

Fix typo when inlining filter hooks, the type signature is not the same as a filter register config parameter.

Author: vricop

docs/src/content/docs/reference/Hooks/filters.md

@@ -51,7 +51,7 @@ StyleDictionary.registerFilter(myFilter);
 export default {
   hooks: {
     filters: {
-      'my-filter': myFilter,
+      'my-filter': myFilter.filter,
     },
   },
   // ... the rest of the configuration