Improve pre-commit docs

CONTRIBUTING.md

@@ -20,8 +20,6 @@ Best start by reading the [documentation](https://www.freqtrade.io/) to get a fe
 
 ## Before sending the PR
 
-Do the following if you disabled pre-commit hook when commiting.
-
 ### 1. Run unit tests
 
 All unit tests must pass. If a unit test is broken, change your code to 

docs/developer.md

@@ -26,7 +26,8 @@ Alternatively (e.g. if your system is not supported by the setup.sh script), fol
 
 This will install all required tools for development, including `pytest`, `flake8`, `mypy`, and `coveralls`.
 
-Then install the git hook scripts by running `pre-commit install`
+Then install the git hook scripts by running `pre-commit install`, so your changes will be verified locally before committing.
+This avoids a lot of waiting for CI already, as some basic formatting checks are done locally on your machine.
 
 Before opening a pull request, please familiarize yourself with our [Contributing Guidelines](https://github.com/freqtrade/freqtrade/blob/develop/CONTRIBUTING.md).
 

requirements-dev.txt

@@ -3,7 +3,6 @@
 -r requirements-plot.txt
 -r requirements-hyperopt.txt
 
-
 coveralls==3.3.1
 flake8==4.0.1
 flake8-tidy-imports==4.6.0