aider: Import CompletedProcess from the subprocess module to fix NameError in test_check_for_ctags_success.

# Context:
USER: pytest tests/test_repomap.py
ASSISTANT: I'm an AI language model and cannot execute commands directly. However,
^C KeyboardInterrupt
USER: I ran this command:

 pytest tests/test_repomap.py

And got this output:

============================= test session starts ==============================
platform darwin -- Python 3.11.3, pytest-7.3.1, pluggy-1.0.0
rootdir: /Users/gauthier/Projects/aider
collected 5 items

tests/test_repomap.py .F...                                              [100%]

=================================== FAILURES ===================================
___________________ TestRepoMap.test_check_for_ctags_success ___________________

self = <tests.test_repomap.TestRepoMap testMethod=test_check_for_ctags_success>

    def test_check_for_ctags_success(self):
        with patch("subprocess.run") as mock_run:
>           mock_run.return_value = CompletedProcess(args=["ctags", "--version"], returncode=0, stdout="Exuberant Ctags 5.8")
E           NameError: name 'CompletedProcess' is not defined

tests/test_repomap.py:67: NameError
=========================== short test summary info ============================
FAILED tests/test_repomap.py::TestRepoMap::test_check_for_ctags_success - Nam...
========================= 1 failed, 4 passed in 0.43s ==========================

ASSISTANT: It looks like there's a `NameError` because `CompletedProcess` is not defined. To fix this, you need to import `CompletedProcess` from the `subprocess` module. Here's the change:

```python
tests/test_repomap.py
<<<<<<< ORIGINAL
from unittest.mock import patch
=======
from unittest.mock import patch
from subprocess import CompletedProcess
>>>>>>> UPDATED
```

This change imports `CompletedProcess` from the `subprocess` module, which should resolve the `NameError`. After making this change, try running the tests again.

tests/test_repomap.py

@@ -3,6 +3,7 @@ import tempfile
 import unittest
 from aider.repomap import RepoMap
 from unittest.mock import patch
+from subprocess import CompletedProcess
 
 class TestRepoMap(unittest.TestCase):
     def test_get_tags_map(self):