update PSReadLine to 2.0.0-beta3 (#7711)
update PSReadLine to 2.0.0-beta3 (#7711)

Update PSReadLine shipped with PSCore6 to 2.0.0-beta3
PaulHigin/PowerShell,JamesWTruher/PowerShell-1,TravisEz13/PowerShell,daxian-dbw/PowerShell,daxian-dbw/PowerShell,daxian-dbw/PowerShell,TravisEz13/PowerShell,JamesWTruher/PowerShell-1,PaulHigin/PowerShell,TravisEz13/PowerShell,PaulHigin/PowerShell,PaulHigin/PowerShell,daxian-dbw/PowerShell,JamesWTruher/PowerShell-1,TravisEz13/PowerShell,JamesWTruher/PowerShell-1