chore(deps): update containrrr/watchtower docker tag to v1.7.1 (#656)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| containrrr/watchtower | patch | `1.7.0` -> `1.7.1` |

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Reviewed-on: #656
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docker-compose/watchtower/docker-compose.yml.j2

@@ -3,7 +3,7 @@ services:
   watchtower:
     restart: always
     container_name: watchtower
-    image: containrrr/watchtower:1.7.0
+    image: containrrr/watchtower:1.7.1@sha256:6dd50763bbd632a83cb154d5451700530d1e44200b268a4e9488fefdfcf2b038
     volumes:
       - /var/run/docker.sock:/var/run/docker.sock
     environment: