I am getting the following warning in all my projects for some time, but I can’t find where to remove the duplicated configuration.
Self-hosted SonarQube 10.1 Developer Edition
Use of sonar.test.exclusions and sonar.tests.exclusions at the same time. sonar.test.exclusions is taken into account.
Consider updating your configuration
If this is happening for all your projects, I would guess that something has been erroneously set in your global Administration > Analysis Scope in the SonarQube UI. Can you check there?