fix: check file storage manager npe

Signed-off-by: alperozturk <[email protected]>

Author: alperozturk96

app/src/main/java/com/owncloud/android/ui/fragment/FileDetailSharingFragment.java

@@ -172,7 +172,12 @@ private void fetchSharees() {
             return;
         }
 
-        ShareRepository shareRepository = new RemoteShareRepository(clientRepository, activity, fileDataStorageManager);
+        final var storageManager = fileDataStorageManager;
+        if (storageManager == null) {
+            return;
+        }
+
+        ShareRepository shareRepository = new RemoteShareRepository(clientRepository, activity, storageManager);
         shareRepository.fetchSharees(file.getRemotePath(), () -> {
             refreshCapabilitiesFromDB();
             refreshSharesFromDB();