DOC: Update Release guidelines

RELEASE_GUIDELINES.md

@@ -18,7 +18,7 @@ guidelines of the CaosDB Project
 
 3. Update the versions in:
   * `CHANGELOG.md`
-  * ?
+  * `compose/docker-compose.yml` in the `caosdb-server.image` section
 
 5. Merge the release branch into the main branch.
 
@@ -26,16 +26,19 @@ guidelines of the CaosDB Project
 
 7. Delete the release branch.
 
-8. Merge the main branch back into the dev branch.
+8. Merge the main branch back into the dev branch and set the image tag to a `-dev` version.
 
-9. Update the versions for the next developement round:
+9. Build the docker image according to the [`README_SETUP.md`](README_SETUP.md),
+   tag it as `caosdb/caosdb:<version>`, and push it to docker hub.
+
+10. Update the versions for the next developement round:
   * `CHANGELOG.md`: Re-add the `[Unreleased]` section.
-  * ?
 
-10. Add a gitlab release in the respective repository:
-    https://gitlab.indiscale.com/caosdb/src/caosdb-server/-/releases
+11. Add a gitlab release in the respective repository:
+    https://gitlab.indiscale.com/caosdb/src/caosdb-docker/-/releases
 
     Add a description, which can be a copy&paste from the CHANGELOG, possibly prepended by:
+
     ```md
 # Changelog