react-reconciler: Update README.md (#13953)
react-reconciler: Update README.md (#13953)

Replaced 'var' with 'const'
TheBlasfem/react,camsong/react,yungsters/react,kaushik94/react,nhunzaker/react,STRML/react,rickbeerendonk/react,chicoxyzzy/react,camsong/react,STRML/react,jameszhan/react,glenjamin/react,TheBlasfem/react,nhunzaker/react,flarnie/react,STRML/react,mjackson/react,ericyang321/react,cpojer/react,billfeller/react,kaushik94/react,tomocchino/react,jameszhan/react,acdlite/react,yungsters/react,billfeller/react,trueadm/react,ericyang321/react,tomocchino/react,jzmq/react,terminatorheart/react,VioletLife/react,yiminghe/react,ArunTesco/react,camsong/react,glenjamin/react,yungsters/react,mosoft521/react,Simek/react,VioletLife/react,ArunTesco/react,STRML/react,jzmq/react,jameszhan/react,acdlite/react,mosoft521/react,chenglou/react,chenglou/react,cpojer/react,billfeller/react,jameszhan/react,trueadm/react,terminatorheart/react,rricard/react,nhunzaker/react,chicoxyzzy/react,jzmq/react,cpojer/react,rricard/react,acdlite/react,chicoxyzzy/react,cpojer/react,mjackson/react,rricard/react,Simek/react,yiminghe/react,rickbeerendonk/react,rricard/react,STRML/react,chicoxyzzy/react,facebook/react,ericyang321/react,rickbeerendonk/react,nhunzaker/react,flarnie/react,flarnie/react,chicoxyzzy/react,flarnie/react,tomocchino/react,trueadm/react,camsong/react,rricard/react,mosoft521/react,billfeller/react,flarnie/react,acdlite/react,yungsters/react,yiminghe/react,glenjamin/react,TheBlasfem/react,jzmq/react,terminatorheart/react,terminatorheart/react,kaushik94/react,tomocchino/react,kaushik94/react,mosoft521/react,mjackson/react,billfeller/react,nhunzaker/react,tomocchino/react,cpojer/react,jzmq/react,mosoft521/react,facebook/react,kaushik94/react,rricard/react,VioletLife/react,flarnie/react,jameszhan/react,glenjamin/react,jdlehman/react,jdlehman/react,camsong/react,facebook/react,billfeller/react,tomocchino/react,cpojer/react,VioletLife/react,ericyang321/react,terminatorheart/react,STRML/react,chenglou/react,yiminghe/react,rickbeerendonk/react,Simek/react,trueadm/react,yiminghe/react,jameszhan/react,tomocchino/react,VioletLife/react,Simek/react,acdlite/react,TheBlasfem/react,Simek/react,jzmq/react,VioletLife/react,flarnie/react,camsong/react,ericyang321/react,chenglou/react,mjackson/react,acdlite/react,mjackson/react,rickbeerendonk/react,jameszhan/react,yungsters/react,chenglou/react,camsong/react,yiminghe/react,VioletLife/react,glenjamin/react,ericyang321/react,glenjamin/react,Simek/react,jdlehman/react,facebook/react,chicoxyzzy/react,facebook/react,nhunzaker/react,trueadm/react,Simek/react,STRML/react,trueadm/react,kaushik94/react,TheBlasfem/react,facebook/react,nhunzaker/react,billfeller/react,yiminghe/react,jdlehman/react,jdlehman/react,mjackson/react,ArunTesco/react,chenglou/react,rickbeerendonk/react,yungsters/react,chicoxyzzy/react,trueadm/react,kaushik94/react,yungsters/react,acdlite/react,ericyang321/react,cpojer/react,terminatorheart/react,jdlehman/react,TheBlasfem/react,jdlehman/react,mjackson/react,glenjamin/react,rickbeerendonk/react,mosoft521/react,chenglou/react,facebook/react,mosoft521/react,jzmq/react