`needs-no-backport` issue label?

[sobolevn]

The short story

It would be nice if there was needs-no-backport issue label.

Long version

Why do we need one?
Right now we only have these backport labels:

All of them target a specific python version. But, sometimes some improvements / fixes (not just features) are not meant to be backported. Right now there's no way to specify this (other than in text description).

Maybe we can add this label to make this intent more obvious? 🤔