Improve error log if root test suite can't be detected

[mikepenz]

• include file when no root test suite can be deteced
  • Relates to Error reported despite successfully parsing the result #1255

[github-actions]

	Tests	Passed ✅	Skipped ⏭️	Failed ❌
Example Pytest Report	4 ran	2 passed	0 skipped	2 failed

Test	Result
Example Pytest Report
test_sample.test_which_succeeds	✅ pass
test_sample.test_which_fails	❌ failure
test_sample.test_with_error	❌ failure
test_sample.test_with_flaky_success	✅ pass

[github-actions]

	Tests	Passed ✅	Skipped ⏭️	Failed ❌
Example Nested JUnit Test Report	3 ran	3 passed	0 skipped	0 failed

Test	Result
Example Nested JUnit Test Report
ABC-0199: XMPP Ping
PingIntegrationTest.pingAsync (Normal)	✅ pass
PingIntegrationTest.pingServer (Normal)	✅ pass
ABC-0045: Multi-User Chat
MultiUserIntegrationTest.mucRoleTestForReceivingModerator (Normal)	✅ pass