[server-pro] move revision from /var/www/revisions.txt into label (#27071)

Co-authored-by: Brian Gough <brian.gough@overleaf.com>
GitOrigin-RevId: d760498b50006a23f446a91647954d00fa22f2f2

server-ce/Dockerfile

@@ -115,9 +115,3 @@ ENV LOG_LEVEL="info"
 EXPOSE 80
 
 ENTRYPOINT ["/sbin/my_init"]
-
-# Store the revision
-# ------------------
-# This should be the last step to optimize docker image caching.
-ARG MONOREPO_REVISION
-RUN echo "monorepo-server-ce,$MONOREPO_REVISION" > /var/www/revisions.txt

server-ce/Makefile

@@ -33,7 +33,7 @@ build-community:
 	  --build-arg BUILDKIT_INLINE_CACHE=1 \
 	  --progress=plain \
 	  --build-arg OVERLEAF_BASE_TAG \
-	  --build-arg MONOREPO_REVISION \
+	  --label "com.overleaf.ce.revision=$(MONOREPO_REVISION)" \
 	  --cache-from $(OVERLEAF_LATEST) \
 	  --cache-from $(OVERLEAF_BRANCH) \
 	  --file Dockerfile \