Unit tests don't run

I updated to Xcode 11.5 from Xcode 11.3.1 and the unit tests for my project will not run anymore. However, I can run the app just fine on the simulator. I get the following error when trying to run the tests:

<MyApp>.app (<app number>) encountered an error (Canceling tests due to timeout in Waiting for test process to check in...)

Since then I've tried everything I can think of:

• Uninstalled and reinstalled 11.3.1, 11.4.1, and 11.5

• Reseting the simulators using "fastlane snapshot reset_simulators".

• Restart computer, restart Xcode, clear derived data folder, clean project - all the usual stuff with Xcode but no luck

The part that really stumps me is that I uninstalled and returned to 11.3.1 and I'm still seeing issues.

Any ideas what could cause the error that I'm seeing?