DOC: Fix double back-tick in 'Reshaping by Melt' section (#17030)
DOC: Fix double back-tick in 'Reshaping by Melt' section (#17030)

See current stable docs for the issue: https://pandas.pydata.org/pandas-docs/stable/reshaping.html#reshaping-by-melt

The double ` is causing the entire paragraph to be fixed width until the next double `. This commit removes the extra "`"
MJuddBooth/pandas,pratapvardhan/pandas,cbertinato/pandas,datapythonista/pandas,nmartensen/pandas,winklerand/pandas,DGrady/pandas,dsm054/pandas,jmmease/pandas,Winand/pandas,cython-testbed/pandas,DGrady/pandas,kdebrab/pandas,zfrenchee/pandas,zfrenchee/pandas,cython-testbed/pandas,jreback/pandas,GuessWhoSamFoo/pandas,MJuddBooth/pandas,DGrady/pandas,toobaz/pandas,TomAugspurger/pandas,louispotok/pandas,nmartensen/pandas,rs2/pandas,amolkahat/pandas,MJuddBooth/pandas,TomAugspurger/pandas,dsm054/pandas,jreback/pandas,louispotok/pandas,pandas-dev/pandas,pratapvardhan/pandas,jorisvandenbossche/pandas,jorisvandenbossche/pandas,jorisvandenbossche/pandas,winklerand/pandas,kdebrab/pandas,louispotok/pandas,jreback/pandas,DGrady/pandas,DGrady/pandas,cbertinato/pandas,cbertinato/pandas,Winand/pandas,amolkahat/pandas,toobaz/pandas,winklerand/pandas,harisbal/pandas,dsm054/pandas,Winand/pandas,MJuddBooth/pandas,jreback/pandas,winklerand/pandas,nmartensen/pandas,Winand/pandas,pratapvardhan/pandas,pandas-dev/pandas,nmartensen/pandas,amolkahat/pandas,gfyoung/pandas,gfyoung/pandas,gfyoung/pandas,toobaz/pandas,TomAugspurger/pandas,harisbal/pandas,jorisvandenbossche/pandas,rs2/pandas,kdebrab/pandas,Winand/pandas,jmmease/pandas,kdebrab/pandas,DGrady/pandas,dsm054/pandas,winklerand/pandas,harisbal/pandas,pratapvardhan/pandas,cbertinato/pandas,toobaz/pandas,kdebrab/pandas,jmmease/pandas,datapythonista/pandas,louispotok/pandas,GuessWhoSamFoo/pandas,jmmease/pandas,cython-testbed/pandas,amolkahat/pandas,cython-testbed/pandas,GuessWhoSamFoo/pandas,pandas-dev/pandas,zfrenchee/pandas,winklerand/pandas,jreback/pandas,MJuddBooth/pandas,pratapvardhan/pandas,amolkahat/pandas,nmartensen/pandas,zfrenchee/pandas,gfyoung/pandas,cython-testbed/pandas,louispotok/pandas,jmmease/pandas,rs2/pandas,TomAugspurger/pandas,jmmease/pandas,datapythonista/pandas,nmartensen/pandas,dsm054/pandas,GuessWhoSamFoo/pandas,toobaz/pandas,harisbal/pandas,GuessWhoSamFoo/pandas,pandas-dev/pandas,rs2/pandas,cbertinato/pandas,zfrenchee/pandas,Winand/pandas,harisbal/pandas,gfyoung/pandas,datapythonista/pandas