Backport of https://github.com/go-gitea/gitea/pull/39934 to release/v28.
Runner token verification (PBKDF2) dominated CPU on instances with many
runners. Successful verifications are now cached in a dedicated LRU.
Conflict resolved by keeping v28's connect v1 interceptor and adding
only the cache.
_Backport prepared with Codet._
Co-authored-by: silverwind <me@silverwind.io>
