DOC: replaced 'Good as first PR' with 'good first issue' (#18806)
DOC: replaced 'Good as first PR' with 'good first issue' (#18806)


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