Fix cppcheck filter to preserve trailing newline

Changed regex from .*\n+ to .*\n to remove the checkers
report line while preserving the trailing newline.

Author: pocc

tests/test_hooks.py

@@ -413,7 +413,7 @@ def run_integration_test(cmd_name, files, args, test_dir, target_output, target_
 
         # Newer cppcheck versions include a checkers report info line
         if cmd_name == "cppcheck":
-            output_actual = re.sub(rb"nofile:0:0: information: Active checkers.*\n+", b"", output_actual)
+            output_actual = re.sub(rb"nofile:0:0: information: Active checkers.*\n", b"", output_actual)
 
         utils.assert_equal(target_output, output_actual)
         assert target_retcode == actual_returncode
@@ -454,7 +454,7 @@ def run_shell_cmd(cmd_name, files, args, _, target_output, target_retcode):
             actual = re.sub(rb"[\d,]+ warnings and ", b"", actual)
         # Newer cppcheck versions include a checkers report info line
         if cmd_name == "cppcheck":
-            actual = re.sub(rb"nofile:0:0: information: Active checkers.*\n+", b"", actual)
+            actual = re.sub(rb"nofile:0:0: information: Active checkers.*\n", b"", actual)
         retcode = sp_child.returncode
         utils.assert_equal(target_output, actual)
         assert target_retcode == retcode