update contributing

docs/CONTRIBUTING.md

@@ -107,4 +107,4 @@ mkdocs gh-deploy
 
 ## Changing dependencies
 
-Is as the development process moves forward you find you need to add a new dependency, just add it to the relevant section of the `pyproject.toml` file and then run `pip-compile` as required to regenerate the different `requirements.txt` files. Read the [`pip-tools` documentation](https://pip-tools.readthedocs.io/en/latest/) for more information on the process.
+Is as the development process moves forward you find you need to add a new dependency, just add it to the relevant section of the `pyproject.toml` file.