Extra unit test

[jethror1]

• add unit test to assert our v1 filtering works as intended

  
  $ python3 -m pytest -v resources/home/dnanexus/generate_workbook/tests/test_filters.py 
  ========================================== test session starts ===========================================
  platform linux -- Python 3.8.10, pytest-7.0.1, pluggy-1.0.0 -- /usr/bin/python3
  cachedir: .pytest_cache
  rootdir: /home/jethro/Projects/eggd_vcf2xls_nirvana
  collected 7 items                                                                                        

resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestModifyingFieldTypes::test_type_correctly_modified PASSED [ 14%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestModifyingFieldTypes::test_header_overwritten_correctly PASSED [ 28%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_include_eq PASSED [ 42%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_exclude_eq PASSED [ 57%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_exclude_gt PASSED [ 71%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_combined_exclude_float_and_string PASSED [ 85%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_combined_filter_and_recover PASSED [100%]

=========================================== 7 passed in 19.27s ===========================================

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[pep8speaks]

Hello @jethror1! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file resources/home/dnanexus/generate_workbook/tests/test_filters.py:

Line 249:80: E501 line too long (83 > 79 characters) Line 252:9: E303 too many blank lines (2) Line 292:57: E502 the backslash is redundant between brackets Line 303:5: E303 too many blank lines (2) Line 355:80: E501 line too long (80 > 79 characters)