chore(deps): pin dependencies (#122)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/library/teamspeak | pinDigest |  → `11fb1dd` |
| ghcr.io/gotify/server | pinDigest |  → `a3af470` |

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Reviewed-on: #122
Reviewed-by: t.behrendt <2+t.behrendt@noreply.localhost>
Co-authored-by: Renovate Bot <renovate@t00n.de>
Co-committed-by: Renovate Bot <renovate@t00n.de>

compose.yaml

@@ -17,7 +17,7 @@ services:
       MODE: '["connect", "disconnect", "moved", "message"]'
 
   gotify:
-    image: ghcr.io/gotify/server:latest
+    image: ghcr.io/gotify/server:latest@sha256:a3af47067ce6aad76aadf5ba32d6ddfecd1ae576a961359f039fd1831e8b7652
     ports:
       - 8080:80
     environment:
@@ -27,7 +27,7 @@ services:
       - "./gotify_data:/app/data"
 
   ts3:
-    image: docker.io/library/teamspeak:latest
+    image: docker.io/library/teamspeak:latest@sha256:11fb1dd03c68ae7b3a8a86c5a08827d01d87a833177ad92ee5c19d7b72d08ce0
     ports:
       - name: voice
         target: 9987