chore(deps): update b3log/siyuan docker tag to v3.1.5 (#2046)

* chore(deps): update b3log/siyuan docker tag to v3.1.5

* 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/siyuan/3.1.5/docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   siyuan:
-    image: b3log/siyuan:v3.1.4
+    image: b3log/siyuan:v3.1.5
     container_name: ${CONTAINER_NAME}
     restart: unless-stopped
     user: '1000:1000'