DOC: fix groupby.rst for building issues
DOC: fix groupby.rst for building issues

closes #14861
closes #14863

zfrenchee/pandas,toobaz/pandas,cbertinato/pandas,cbertinato/pandas,harisbal/pandas,zfrenchee/pandas,nmartensen/pandas,TomAugspurger/pandas,Winand/pandas,amolkahat/pandas,gfyoung/pandas,amolkahat/pandas,pandas-dev/pandas,TomAugspurger/pandas,GuessWhoSamFoo/pandas,jreback/pandas,toobaz/pandas,harisbal/pandas,linebp/pandas,DGrady/pandas,pandas-dev/pandas,GuessWhoSamFoo/pandas,dsm054/pandas,dsm054/pandas,Winand/pandas,rs2/pandas,pratapvardhan/pandas,amolkahat/pandas,jreback/pandas,louispotok/pandas,cython-testbed/pandas,datapythonista/pandas,jreback/pandas,gfyoung/pandas,harisbal/pandas,Winand/pandas,GuessWhoSamFoo/pandas,jorisvandenbossche/pandas,winklerand/pandas,rs2/pandas,zfrenchee/pandas,cbertinato/pandas,winklerand/pandas,GuessWhoSamFoo/pandas,winklerand/pandas,kdebrab/pandas,zfrenchee/pandas,DGrady/pandas,DGrady/pandas,nmartensen/pandas,gfyoung/pandas,dsm054/pandas,amolkahat/pandas,jorisvandenbossche/pandas,pandas-dev/pandas,nmartensen/pandas,linebp/pandas,louispotok/pandas,winklerand/pandas,gfyoung/pandas,pratapvardhan/pandas,kdebrab/pandas,Winand/pandas,kdebrab/pandas,nmartensen/pandas,MJuddBooth/pandas,DGrady/pandas,jmmease/pandas,datapythonista/pandas,winklerand/pandas,louispotok/pandas,Winand/pandas,kdebrab/pandas,jmmease/pandas,cython-testbed/pandas,amolkahat/pandas,MJuddBooth/pandas,harisbal/pandas,louispotok/pandas,winklerand/pandas,TomAugspurger/pandas,toobaz/pandas,nmartensen/pandas,gfyoung/pandas,MJuddBooth/pandas,MJuddBooth/pandas,GuessWhoSamFoo/pandas,linebp/pandas,dsm054/pandas,zfrenchee/pandas,pandas-dev/pandas,toobaz/pandas,jmmease/pandas,jmmease/pandas,datapythonista/pandas,MJuddBooth/pandas,cython-testbed/pandas,TomAugspurger/pandas,linebp/pandas,jmmease/pandas,rs2/pandas,cbertinato/pandas,dsm054/pandas,cbertinato/pandas,jorisvandenbossche/pandas,jreback/pandas,datapythonista/pandas,harisbal/pandas,jreback/pandas,pratapvardhan/pandas,Winand/pandas,louispotok/pandas,DGrady/pandas,DGrady/pandas,pratapvardhan/pandas,linebp/pandas,nmartensen/pandas,linebp/pandas,toobaz/pandas,rs2/pandas,jmmease/pandas,kdebrab/pandas,jorisvandenbossche/pandas,cython-testbed/pandas,cython-testbed/pandas,pratapvardhan/pandas