testBusinessTemplate: cancel failed activites at end of test

This prevents one failing test to make all subsequent tests to fail
4 jobs for fix/python3-test-framework in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-TestRunner1

04:05:17

failed ERP5.PerformanceTest-TestRunner1

00:35:44

passed ERP5.UnitTest-TestRunner1

08:18:30

passed ERP5.UnitTest-TestRunner1

05:45:51