Update caddy:2 Docker digest to 9068f76 (#1609)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

docker-compose.yml

@@ -273,7 +273,7 @@ services:
           - bob.test
           - charlie.test
           - fake-external-activitypub.test
-    image: caddy:2@sha256:c3d7ee5d2b11f9dc54f947f68a734c84e9c9666c92c88a7f30b9cba5da182adb
+    image: caddy:2@sha256:9068f76202c0a03545036d32bf2d424d3b46c1174f254070f605002a2dbc9657
     ports:
       - "444:443"
     volumes: