fix: cannot define a join field when the target relationship is nested to a second or higher tab (#12041)

Fixes https://github.com/payloadcms/payload/issues/11720

test/joins/collections/Categories.ts

@@ -162,6 +162,12 @@ export const Categories: CollectionConfig = {
         isFiltered: { not_equals: true },
       },
     },
+    {
+      name: 'inTab',
+      type: 'join',
+      collection: postsSlug,
+      on: 'tab.category',
+    },
     {
       name: 'joinWithError',
       type: 'join',