gh-120568: fix file leak in PyUnstable_CopyPerfMapFile

[carsonRadtke]

Fixes a file leak in PyUnstable_CopyPerfMapFile found by the Clang Static Analyzer.

• Issue: file leak in PyUnstable_CopyPerfMapFile #120568

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Windows11 Bigmem 3.x has failed when building commit 92cebaa.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/1079/builds/4239) and take a look at the build logs.
4. Check if the failure is related to this commit (92cebaa) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/1079/builds/4239

Failed tests:

• test_repl

Failed subtests:

• test_asyncio_repl_is_ok - test.test_repl.TestInteractiveInterpreter.test_asyncio_repl_is_ok

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "R:\buildarea\3.x.ambv-bb-win11.bigmem\build\Lib\test\test_repl.py", line 199, in test_asyncio_repl_is_ok
    assert_python_ok("-m", "asyncio")
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "R:\buildarea\3.x.ambv-bb-win11.bigmem\build\Lib\test\support\script_helper.py", line 180, in assert_python_ok
    return _assert_python(True, *args, **env_vars)
  File "R:\buildarea\3.x.ambv-bb-win11.bigmem\build\Lib\test\support\script_helper.py", line 165, in _assert_python
    res.fail(cmd_line)
    ~~~~~~~~^^^^^^^^^^
  File "R:\buildarea\3.x.ambv-bb-win11.bigmem\build\Lib\test\support\script_helper.py", line 75, in fail
    raise AssertionError("Process return code is %d\n"
    ...<13 lines>...
                            err))
AssertionError: Process return code is 2147483651
command line: ['R:\\buildarea\\3.x.ambv-bb-win11.bigmem\\build\\PCbuild\\amd64\\python_d.exe', '-X', 'faulthandler', '-I', '-m', 'asyncio']