Cartopy and Codecov pytest --cov does not work for python 3.14

[zssherman]

Currently we get a 'shim' error when running pytest --cov for the cartopy plot tests. Adding a skip for those tests for python 3.14 until we can determine the cause or if its a simple as waiting for a new cartopy or coverage release:

FAILED tests/graph/test_gridmapdisplay.py::test_gridmapdisplay_simple - SystemError: cannot instrument shim code object 'project_linear'
FAILED tests/graph/test_gridmapdisplay.py::test_gridmapdisplay_fancy - SystemError: cannot instrument shim code object '_interpolator'
FAILED tests/graph/test_plot_maxcappi.py::test_plot_maxcappi_simple - SystemError: cannot instrument shim code object 'cinit'
FAILED tests/graph/test_plot_maxcappi.py::test_plot_maxcappi_with_save - SystemError: cannot instrument shim code object 'init'
FAILED tests/graph/test_plot_maxcappi.py::test_plot_maxcappi_with_all_options - SystemError: cannot instrument shim code object 'project_points'
FAILED tests/graph/test_radarmapdisplay.py::test_radarmapdisplay_cartopy_ppi - SystemError: cannot instrument shim code object 'init'