Update documentation.

doc/developer_guide/continuous_integration.md

@@ -46,4 +46,5 @@ The following CI jobs are used for building our software for different target pl
 The CI jobs listed below are run periodically to perform different maintenance tasks, such as the automatic update of dependencies.
 
 - `update_github_actions.yml` checks for outdated GitHub Actions used in workflow definition files. In cases where any updates are necessary, a pull request with the respective changes is opened. If the pull request passes all {ref}`necessary checks <ci-testing>`, it is merged automatically. Otherwise, manual intervention is needed.
+- `update_dependencies_build.yml` and `update_dependencies_runtime.yml` searches for outdated build- and runtime dependencies, required by the project's build system and for running its algorithms, respectively. If such dependencies have been found in the project's `requirements.txt` files, a pull request for updating them is opened. If all {ref}`necessary checks <ci-testing>` are successful, the pull request is merged. Otherwise, manual intervention is needed.
 - `update_doxyfile.yml` updates the [Doxygen](https://sourceforge.net/projects/doxygen/) configuration file, required for generating API documentations for C++ code, to stay up-to-date as new versions of this software are released.