fix(unittest): handle error outside of file

If an error occurs outside of the test file, there is no frame to match
an error to. This can happen for example when required arguments are not
passed to the test.

neotest_python/unittest.py

@@ -72,11 +72,10 @@ class UnittestNeotestAdapter(NeotestAdapter):
                     if case_id in errs:
                         trace = errs[case_id][2]
                         summary = traceback.extract_tb(trace)
-                        error_line = next(
-                            frame.lineno - 1
-                            for frame in reversed(summary)
-                            if frame.filename == case_file
-                        )
+                        for frame in reversed(summary):
+                            if frame.filename == case_file:
+                                error_line = frame.lineno - 1
+                                break
                     results[case_id] = {
                         "status": NeotestResultStatus.FAILED,
                         "errors": [{"message": message, "line": error_line}],