chore(deps): update dependency jeboehm/mailserver-admin to v5.4.18 (#448)

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

Author: renovate[bot]

web/Dockerfile

@@ -66,7 +66,7 @@ RUN --mount=type=cache,target=/root/.composer \
         ${RC_PLUGINS}; \
     fi
 
-ARG ADMIN_VER=5.4.17 # renovate: depName=jeboehm/mailserver-admin
+ARG ADMIN_VER=5.4.18 # renovate: depName=jeboehm/mailserver-admin
 RUN --mount=type=cache,target=/root/.composer \
     mkdir /opt/manager && \
     cd /opt/manager && \