fix(docs): updated instructions for releases

docs/How_to_contribute.md

@@ -48,7 +48,7 @@ Execute the following steps in order to create a new DiscoPoP release:
 - Switch to the release branch (e.g. `release/1.2.3`) which shall be released
 - Update the version file in the repository (`discopop_library/global_data/version/VERSION`)
 - Create a pull request to the `master` branch and validate the changes
-- Merge the pull request and create a tag on the `master` branch with the name `v1.2.3`
+- Merge the pull request by rebasing and create a tag on the `master` branch with the name `v1.2.3`
     - Creating the tag triggers the automatic publication of the project to PyPi
     - Creating the tag triggers the automatic creation of a release draft
 - Update the newly created release draft