Fix tests

[smaret]

Fix tests with Astrochem 5.1 (#156) and Numpy 1.23 (#158).

[smaret]

CI still fails, but pytest reports no errors.

==================================== test session starts ====================================
platform darwin -- Python 3.10.6, pytest-7.1.3, pluggy-1.0.0
rootdir: /Users/smaret/Documents/Software/pyregion, configfile: setup.cfg
plugins: hypothesis-6.54.6, remotedata-0.3.3, astropy-header-0.2.2, doctestplus-0.12.1, mock-3.8.2, astropy-0.10.0, filter-subpackage-0.1.1, openfiles-0.5.0, cov-3.0.0, arraydiff-0.5.0
collected 45 items                                                                          

pyregion/tests/test_cube.py .                                                         [  2%]
pyregion/tests/test_ds9_attr_parser.py ...                                            [  8%]
pyregion/tests/test_ds9_region_parser.py ....                                         [ 17%]
pyregion/tests/test_get_mask.py .                                                     [ 20%]
pyregion/tests/test_parser_helper.py .                                                [ 22%]
pyregion/tests/test_region.py ......................                                  [ 71%]
pyregion/tests/test_region_numbers.py .......                                         [ 86%]
pyregion/tests/test_wcs.py ......                                                     [100%]

===================================== warnings summary ======================================
pyregion/tests/test_region.py::test_open_regions[test01.reg]
  /Users/smaret/Documents/Software/pyregion/pyregion/ds9_region_parser.py:107: UserWarning: Failed to parse : ascircle(171.10096,-59.250612,18.510811") # color=cyan
    warnings.warn("Failed to parse : " + l)

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
=============================== 45 passed, 1 warning in 4.81s ===============================