Fix test_bibtex unit test

[arunkannawadi]

Describe the bug
The test_bibtex unit test with failing, with a cryptic traceback

Screenshots

======================================================================
FAIL: test_bibtex (test_module.TestScholarly)
Test that we get the BiBTeX entry correctly
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Traceback (most recent call last):
  File "/home/runner/work/scholarly/scholarly/test_module.py", line 233, in test_bibtex
    self.assertEqual(result, expected_result.replace("\n        ", "\n"))
AssertionError: '@inp[134 chars]ses.  However, the well-known algorithms suffe[4[71](https://github.com/scholarly-python-package/scholarly/runs/5045402146?check_suite_focus=true#step:8:71) chars]\n\n' != '@inp[134 chars]ses. However, the application to large spatial[457 chars]\n\n'
Diff is 960 characters long. Set self.maxDiff to None to see it.

Desktop (please complete the following information):
Github Action

Do you plan on contributing?

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