OAuth2: add Yandex provider (#8335) (#10564)

* OAuth2: add Yandex provider (#8335)

* remove changes from locale ru-RU

* fmt modules/auth/oauth2/oauth2.go

Co-Authored-By: 6543 <6543@obermui.de>

* fix fmt

* Update templates/admin/auth/new.tmpl

* fix fmt

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: guillep2k <18600385+guillep2k@users.noreply.github.com>
Co-authored-by: techknowlogick <matti@mdranta.net>
Co-authored-by: Lauris BH <lauris@nix.lv>

options/locale/locale_en-US.ini

@@ -1937,6 +1937,7 @@ auths.tip.openid_connect = Use the OpenID Connect Discovery URL (<server>/.well-
 auths.tip.twitter = Go to https://dev.twitter.com/apps, create an application and ensure that the “Allow this application to be used to Sign in with Twitter” option is enabled
 auths.tip.discord = Register a new application on https://discordapp.com/developers/applications/me
 auths.tip.gitea = Register a new OAuth2 application. Guide can be found at https://docs.gitea.io/en-us/oauth2-provider/
+auths.tip.yandex = Create a new application at https://oauth.yandex.com/client/new. Select following permissions from the "Yandex.Passport API" section: "Access to email address", "Access to user avatar" and "Access to username, first name and surname, gender"
 auths.edit = Edit Authentication Source
 auths.activated = This Authentication Source is Activated
 auths.new_success = The authentication '%s' has been added.