Add instructions on how to release a new version

Author: sandhose

README.md

@@ -9,3 +9,16 @@ Functionality constraints:
 - the in progress rendezvous do not need to be persisted between server restarts
 - the server does not need to work in a clustered/sharded deployment
 - no authentication is needed for use of the server
+
+### Releasing
+
+```sh
+git checkout main
+cargo set-version --workspace --bump patch
+cd synapse/
+poetry version patch
+cd ..
+git commit -m "vX.Y.Z"
+git tag vX.Y.Z
+git push
+git push --tags