Unclosed file causes ResourceWarning while running unit tests

[dlebedinsky]

Describe the bug
I fixed the test_bibtex unit test in my last PR #525. My only change was to the name of the input file. When I initially ran the unit test, it was working, but when I reran today, the test had a ResourceWarning and an error, because apparently a file is left open? There was also a similar ResourceWarning following the test_citedby_1k_citations, but that test did not give an error result.

To Reproduce
Run python -m unittest -v test_module.py

Expected behavior
I expected to see the following:
test_bibtex (test_module.TestScholarlyWithProxy.test_bibtex)
Test that we get the BiBTeX entry correctly ... ok
test_citedby_1k_citations (test_module.TestScholarlyWithProxy.test_citedby_1k_citations)
Test that scholarly can fetch 1000+ citations from an author ... ok

or at the very least, just: "Test that we get the BiBTeX entry correctly ... FAIL"

Stack trace
test_bibtex (test_module.TestScholarlyWithProxy.test_bibtex)
Test that we get the BiBTeX entry correctly ... /usr/lib64/python3.11/threading.py:101: ResourceWarning: unclosed file <_io.FileIO name='/dev/null' mode='wb' closefd=True>
return _CRLock(*args, **kwargs)
ResourceWarning: Enable tracemalloc to get the object allocation traceback
/usr/lib/python3.11/site-packages/urllib3/connection.py:242: ResourceWarning: unclosed file <_io.FileIO name='/dev/null' mode='wb' closefd=True>
if "user-agent" not in (six.ensure_str(k.lower()) for k in headers):
ResourceWarning: Enable tracemalloc to get the object allocation traceback
ERROR

test_citedby_1k_citations (test_module.TestScholarlyWithProxy.test_citedby_1k_citations)
Test that scholarly can fetch 1000+ citations from an author ... :947: ResourceWarning: unclosed file <_io.FileIO name='/dev/null' mode='wb' closefd=True>
ResourceWarning: Enable tracemalloc to get the object allocation traceback
ok

======================================================================
ERROR: test_bibtex (test_module.TestScholarlyWithProxy.test_bibtex)
Test that we get the BiBTeX entry correctly

Traceback (most recent call last):
File "/home/daniel/repos/scholarly-dev/test_module.py", line 696, in test_bibtex
pub = scholarly.search_single_pub("A distribution-based clustering algorithm for mining in large "
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/daniel/repos/scholarly-dev/scholarly/_scholarly.py", line 182, in search_single_pub
return self.__nav.search_publication(url, filled)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/daniel/repos/scholarly-dev/scholarly/_navigator.py", line 281, in search_publication
soup = self._get_soup(url)
^^^^^^^^^^^^^^^^^^^
File "/home/daniel/repos/scholarly-dev/scholarly/_navigator.py", line 239, in _get_soup
html = self._get_page('https://scholar.google.com{0}'.format(url))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/daniel/repos/scholarly-dev/scholarly/_navigator.py", line 190, in _get_page
raise MaxTriesExceededException("Cannot Fetch from Google Scholar.")
scholarly._proxy_generator.MaxTriesExceededException: Cannot Fetch from Google Scholar.

Desktop (please complete the following information):

• Proxy service: free-proxy
• python version: 3.11.6
• OS: Fedora Linux 38

Do you plan on contributing?
Your response below will clarify whether the maintainers can expect you to fix the bug you reported.

• Yes, I will create a Pull Request with the bugfix.

Additional context
I noticed that test_module.py automatically generated a CSV, in the same directory as itself. It is attached, I am not sure if it is intended behavior, or if it is relevant to this error.
bsvrngkuqu.csv