fix: Python 3 crash in googletest-output-test.py debug mode

Fixes #3943

Change file open mode from 'wb' (binary) to 'w' (text) when writing
normalized output in DEBUG_GTEST_OUTPUT_TEST mode.

googletest/test/googletest-output-test.py

diff --git a/googletest/test/googletest-output-test.py b/googletest/test/googletest-output-test.py
index 6d80d53..812197b 100755
--- a/googletest/test/googletest-output-test.py
+++ b/googletest/test/googletest-output-test.py
@@ -349,14 +349,14 @@
                 gtest_test_utils.GetSourceDir(),
                 '_googletest-output-test_normalized_actual.txt',
             ),
-            'wb',
+            'w',
         ).write(normalized_actual)
         open(
             os.path.join(
                 gtest_test_utils.GetSourceDir(),
                 '_googletest-output-test_normalized_golden.txt',
             ),
-            'wb',
+            'w',
         ).write(normalized_golden)
 
       self.assertEqual(normalized_golden, normalized_actual)