CI: Set GMT_ENABLE_OPENMP to TRUE to enable OpenMP support on macOS

[seisman]

After upstream fix GenericMappingTools/gmt#8494, now it's possible to enable OpenMP support on macOS.

[seisman]

Now, there is only one failure on Linux/macOS/Windows:

=================================== FAILURES ===================================
__________________________ test_compute_bins_outfile ___________________________
[gw1] linux -- Python 3.12.3 /home/runner/micromamba/envs/pygmt/bin/python

grid = <xarray.DataArray 'z' (lat: 14, lon: 8)> Size: 448B
array([[347.5, 344.5, 386. , 640.5, 617. , 579. , 646.5, 671. ],
 ...3.5 -22.5 -21.5 -20.5 ... -12.5 -11.5 -10.5
Attributes:
    long_name:     elevation (m)
    actual_range:  [190. 981.]
expected_df =    start   stop  bin_id
0  345.5  519.5       0
1  519.5  726.5       1
region = [-52, -48, -22, -18]

    def test_compute_bins_outfile(grid, expected_df, region):
        """
        Test grdhisteq.compute_bins with ``outfile``.
        """
        with GMTTempFile(suffix=".txt") as tmpfile:
            with pytest.warns(RuntimeWarning) as record:
                result = grdhisteq.compute_bins(
                    grid=grid,
                    divisions=2,
                    region=region,
                    outfile=tmpfile.name,
                )
                assert len(record) == 1  # check that only one warning was raised
            assert result is None  # return value is None
            assert Path(tmpfile.name).stat().st_size > 0
            temp_df = pd.read_csv(
                filepath_or_buffer=tmpfile.name,
                sep="\t",
                header=None,
                names=["start", "stop", "bin_id"],
                dtype={"start": np.float32, "stop": np.float32, "bin_id": np.uint32},
                index_col="bin_id",
            )
>           pd.testing.assert_frame_equal(
                left=temp_df, right=expected_df.set_index("bin_id")
            )

../pygmt/tests/test_grdhisteq.py:130: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

left = RangeIndex(start=0, stop=2, step=1, name='bin_id')
right = Index([0, 1], dtype='uint32', name='bin_id'), obj = 'DataFrame.index'

    def _check_types(left, right, obj: str = "Index") -> None:
        if not exact:
            return
    
        assert_class_equal(left, right, exact=exact, obj=obj)
        assert_attr_equal("inferred_type", left, right, obj=obj)
    
        # Skip exact dtype checking when `check_categorical` is False
        if isinstance(left.dtype, CategoricalDtype) and isinstance(
            right.dtype, CategoricalDtype
        ):
            if check_categorical:
                assert_attr_equal("dtype", left, right, obj=obj)
                assert_index_equal(left.categories, right.categories, exact=exact)
            return
    
>       assert_attr_equal("dtype", left, right, obj=obj)
E       AssertionError: DataFrame.index are different
E       
E       Attribute "dtype" are different
E       [left]:  int64
E       [right]: uint32

[weiji14]

Nice! Thanks for getting OpenMP support to work on macOS upstream!