test(bump_command): replace \ as / for windows test cases

Author: Lee-W

tests/commands/test_bump_command.py

@@ -349,6 +349,7 @@ def test_bump_major_version_zero_when_major_is_not_zero(mocker, tmp_commitizen_p
     tmp_version_file = tmp_commitizen_project.join("__version__.py")
     tmp_version_file.write("1.0.0")
     tmp_commitizen_cfg_file = tmp_commitizen_project.join("pyproject.toml")
+    tmp_version_file_string = str(tmp_version_file).replace("\\", "/")
     tmp_commitizen_cfg_file.write(
         f"[tool.commitizen]\n"
         'version="1.0.0"\n'