Added what seems to be another dependency issue to OpenMM docs building.
Added what seems to be another dependency issue to OpenMM docs building.


Former-commit-id: b45d8b0e5cc085d749af60f599fd594c097d1bfd
swails/conda-recipes,danielparton/omnia-md-conda-recipes,rmcgibbo/conda-recipes,marscher/omnia-conda-recipes,danielparton/omnia-md-conda-recipes,jchodera/conda-recipes,swails/conda-recipes,peastman/conda-recipes,peastman/conda-recipes,jchodera/conda-recipes,jchodera/conda-recipes,rmcgibbo/conda-recipes,jchodera/conda-recipes,mpharrigan/conda-recipes,cwehmeyer/conda-recipes,rmcgibbo/conda-recipes,mpharrigan/conda-recipes,cwehmeyer/conda-recipes,swails/conda-recipes,cwehmeyer/conda-recipes,marscher/omnia-conda-recipes,swails/conda-recipes,marscher/omnia-conda-recipes,marscher/omnia-conda-recipes,cwehmeyer/conda-recipes,peastman/conda-recipes,omnia-md/conda-recipes,mpharrigan/conda-recipes,rmcgibbo/conda-recipes,omnia-md/conda-recipes,omnia-md/conda-recipes