DOC: update the RegularGridInterpolator docstring (#16264)
DOC: update the RegularGridInterpolator docstring (#16264)

DOC: update the RegularGridInterpolator docstring

Co-authored-by: Matt Haberland <1f6e3f9dd4f3b851e1c9f994a33220fb712394f1@calpoly.edu>
mdhaber/scipy,endolith/scipy,ilayn/scipy,scipy/scipy,ilayn/scipy,rgommers/scipy,perimosocordiae/scipy,Stefan-Endres/scipy,andyfaff/scipy,WarrenWeckesser/scipy,anntzer/scipy,andyfaff/scipy,ilayn/scipy,scipy/scipy,perimosocordiae/scipy,endolith/scipy,scipy/scipy,rgommers/scipy,andyfaff/scipy,ilayn/scipy,mdhaber/scipy,WarrenWeckesser/scipy,endolith/scipy,mdhaber/scipy,Stefan-Endres/scipy,perimosocordiae/scipy,rgommers/scipy,ilayn/scipy,perimosocordiae/scipy,rgommers/scipy,scipy/scipy,Stefan-Endres/scipy,ilayn/scipy,perimosocordiae/scipy,andyfaff/scipy,andyfaff/scipy,mdhaber/scipy,andyfaff/scipy,Stefan-Endres/scipy,rgommers/scipy,Stefan-Endres/scipy,anntzer/scipy,anntzer/scipy,WarrenWeckesser/scipy,anntzer/scipy,scipy/scipy,endolith/scipy,scipy/scipy,WarrenWeckesser/scipy,anntzer/scipy,anntzer/scipy,mdhaber/scipy,endolith/scipy,perimosocordiae/scipy,mdhaber/scipy,WarrenWeckesser/scipy,endolith/scipy,WarrenWeckesser/scipy,Stefan-Endres/scipy