chore: fix smbclient setup in ci

Signed-off-by: Robin Appelman <robin@icewind.nl>

Author: icewind1991

.github/workflows/files-external-smb.yml

@@ -95,7 +95,9 @@ jobs:
 
       - name: Set up smbclient
         # This is needed as icewind/smb php library for notify
-        run: sudo apt-get install -y smbclient
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y smbclient
 
       - name: Set up Nextcloud
         run: |