docs: remove copy&paste section

docs/contributing.md

@@ -10,16 +10,3 @@
     * when updating documentation, please see [our guidance for documentation contributions](contributing_docs.md).
     * apply format running `go fmt`, or the shell script `./scripts/checks.sh`
     * verify all tests are passing. Build and test the project with `make test-all` to do this.
-
-## Combining Dependabot PRs
-
-Since we generally get quite a few Dependabot PRs, we regularly combine them into single commits. 
-For this, we are using the [gh-combine-prs](https://github.com/rnorth/gh-combine-prs) extension for [GitHub CLI](https://cli.github.com/).
-
-The whole process is as follow:
-
-1. Check that all open Dependabot PRs did succeed their build. If they did not succeed, trigger a rerun if the cause were external factors or else document the reason if obvious.
-2. Run the extension from an up-to-date local `main` branch: `gh combine-prs --query "author:app/dependabot"`
-3. Merge conflicts might appear. Just ignore them, we will get those PRs in a future run.
-4. Once the build of the combined PR did succeed, temporarily enable merge commits and merge the PR using a merge commit through the GitHub UI.
-5. After the merge, disable merge commits again.