chore(deps): update hub.zentao.net/app/zentao docker tag to v20.4 (#1855)

* chore(deps): update hub.zentao.net/app/zentao docker tag to v20.4

* Update app version [skip ci]

---------

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: github-action update-app-version <githubaction@githubaction.com>

apps/zentao/20.4/docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   zentao:
-    image: hub.zentao.net/app/zentao:20.0
+    image: hub.zentao.net/app/zentao:20.4
     container_name: ${CONTAINER_NAME}
     restart: always
     ports: