fix broken unit tests

[jethror1]

• Fix broken test due to previous change in FOMRAT column suffix from (FMT) to _FMT
• Align all tests to use same test data for consistency
• Ignore pytest deprecation warnings raised from required escaping characters in subprocess call to grep that it is picky about but is needed
• All tests pass:

  
  $ python3 -m pytest -v resources/home/dnanexus/generate_workbook/tests/
  ================================================ 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/resources/home/dnanexus/generate_workbook/tests, configfile: pytest.ini
  collected 19 items                                                                                                  

resources/home/dnanexus/generate_workbook/tests/test_columns.py::TestInfoColumn::test_parsed_correct_columns_from_info_records PASSED [ 5%] resources/home/dnanexus/generate_workbook/tests/test_columns.py::TestInfoColumn::test_parsed_correct_gnomADe_AF_values PASSED [ 10%] resources/home/dnanexus/generate_workbook/tests/test_columns.py::TestFormatSample::test_format_sample_values_are_correct PASSED [ 15%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestModifyingFieldTypes::test_type_correctly_modified PASSED [ 21%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestModifyingFieldTypes::test_header_overwritten_correctly PASSED [ 26%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_include_eq PASSED [ 31%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_exclude_eq PASSED [ 36%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_filter_with_exclude_gt PASSED [ 42%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_combined_exclude_float_and_string PASSED [ 47%] resources/home/dnanexus/generate_workbook/tests/test_filters.py::TestFilters::test_combined_filter_and_recover PASSED [ 52%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestHeader::test_column_names PASSED [ 57%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestHeader::test_parse_reference PASSED [ 63%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestHeader::test_only_header_parsed PASSED [ 68%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_drop_columns_exclude PASSED [ 73%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_drop_columns_include PASSED [ 78%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_reorder_columns_correct_order PASSED [ 84%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_reorder_columns_no_dropped_columns PASSED [ 89%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_non_rename_columns_unaffacted PASSED [ 94%] resources/home/dnanexus/generate_workbook/tests/test_vcf.py::TestDataFrameActions::test_renamed_correctly PASSED [100%]

================================================ 19 passed in 27.15s ================================================

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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_columns.py:

Line 71:5: E303 too many blank lines (2) Line 80:35: W605 invalid escape sequence '.' Line 80:38: W605 invalid escape sequence '-' Line 91:80: E501 line too long (81 > 79 characters)