doc: Move CI-must-pass requirement into readme section

Seems fine to state it clearly once.

Author: MarcoFalke

README.md

@@ -56,8 +56,8 @@ in Python.
 These tests can be run (if the [test dependencies](/test) are installed) with: `build/test/functional/test_runner.py`
 (assuming `build` is your build directory).
 
-The CI (Continuous Integration) systems make sure that every pull request is built for Windows, Linux, and macOS,
-and that unit/sanity tests are run automatically.
+The CI (Continuous Integration) systems make sure that every pull request is tested on Windows, Linux, and macOS.
+The CI must pass on all commits before merge to avoid unrelated CI failures on new pull requests.
 
 ### Manual Quality Assurance (QA) Testing
 

doc/developer-notes.md

@@ -798,12 +798,6 @@ General Bitcoin Core
   - *Rationale*: RPC allows for better automatic testing. The test suite for
     the GUI is very limited.
 
-- Make sure pull requests pass CI before merging.
-
-  - *Rationale*: Makes sure that they pass thorough testing, and that the tester will keep passing
-     on the master branch. Otherwise, all new pull requests will start failing the tests, resulting in
-     confusion and mayhem.
-
 Logging
 -------