Running all tests at once causes failure of test for Wrapper.py

[eggplants]

https://github.com/eggplants/sparqlwrapper/runs/4798682454

$ python -m unittest test/test_wrapper.py -v
...
Ran 35 tests in 0.468s

OK (skipped=1)

$ python -m unittest -v
...
======================================================================
FAIL: testConvert (test.test_wrapper.QueryResult_Test)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/runner/work/sparqlwrapper/sparqlwrapper/test/test_wrapper.py", line 886, in testConvert
    self.assertEqual(1, _mime_vs_type("application/x-foo-bar", XML), "invalid mime")
AssertionError: 1 != 0 : invalid mime

======================================================================
FAIL: testPrint_results (test.test_wrapper.QueryResult_Test)
print_results() is only allowed for JSON return format.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/runner/work/sparqlwrapper/sparqlwrapper/test/test_wrapper.py", line 938, in testPrint_results
    self.assertEqual(1, _print_results("application/sparql-results+xml"))
AssertionError: 1 != 0

======================================================================
FAIL: testSetReturnFormat (test.test_wrapper.SPARQLWrapper_Test)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/runner/work/sparqlwrapper/sparqlwrapper/test/test_wrapper.py", line 198, in testSetReturnFormat
    self.assertEqual(1, len(w), "Warning due to non expected format")
AssertionError: 1 != 0 : Warning due to non expected format

----------------------------------------------------------------------
Ran 1335 tests in 845.111s

FAILED (failures=3, skipped=476, expected failures=65)

The reason is unknown...

[eggplants]

This issue is resolved When testing with pytest.
#214