Add return statement in fallback 'set'

Signed-off-by: ivgo <ivgo@spreadgroup.com>

.changeset/clever-ties-burn.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-user-settings': patch
+---
+
+Prevent `.set()` to execute a request to the StorageClient if the user is `guest`

plugins/user-settings/src/apis/StorageApi/UserSettingsStorage.ts

@@ -118,6 +118,7 @@ export class UserSettingsStorage implements StorageApi {
     if (!(await this.isSignedIn())) {
       await this.fallback.set(key, data);
       this.notifyChanges({ key, presence: 'present', value: data });
+      return;
     }
 
     const fetchUrl = await this.getFetchUrl(key);