docs: Add Russian translation

[Hkr32]

Russian translation for Bootstrap 4

[XhmikosR]

@Hkr32 if you have disabled the option for maintainers to edit your PR, please enable it and not disable it again. I see no way of updating the branch right now.

[Hkr32]

@XhmikosR, where can I change this? Everything is default.

[XhmikosR]

https://docs.github.com/en/free-pro-team@latest/github/collaborating-with-issues-and-pull-requests/allowing-changes-to-a-pull-request-branch-created-from-a-fork

There should be a button to update the branch here, but there isn't.

[Hkr32]

No item to allow

[XhmikosR]

Not sure why you don't have the option there. You should see something like this:

Anyway, some weirdness is happening, that's for sure.

[Hkr32]

Maybe I need to update the data?

[XhmikosR]

Like I said there's no button present.

Anyway, no big deal, but you should update your branch.