net/rubygem-gitaly-proto: Mark DEPRECATED and set EXPIRATION_DATE to 2026-05-31

This is an archived project. Repository and other project resources are read-only.

from README.md:
gitaly-proto has been deprecated

PR: 295168
Reference: https://gitlab.com/gitlab-org/gitaly-proto

		https://gitlab.com/gitlab-org/gitaly-proto/-/blob/master/README.md

Approved by: mfechner (maintainer)