Symptom
If a project is created in a version earlier than DevEco Studio 3.1.0.400, after DevEco Studio is upgraded to 3.1.0.400 or later, the project fails to run test cases and the error message "A page configured in 'test_pages.json' must have one and only one '@Entry' decorator" is displayed.
Figure 1
Solution
Rename the TestRunner and TestAbility directories testrunner and testability, which are in lowercase, and run the test cases again.
Figure 2
