REST API: RunnerDetails will no longer return version, revision, platform, architecture

version, revision, platform, and architecture for an individual GitLab runner don't make sense now when we can have multiple runner managers assigned to the same runner with different values.

• Starting from %18.0 they will return "".
• In the Rest API v5 they will be removed

diff --git a/lib/api/entities/ci/runner_details.rb b/lib/api/entities/ci/runner_details.rb
index a26e3afb4c77..ee1ccbe9fffc 100644
--- a/lib/api/entities/ci/runner_details.rb
+++ b/lib/api/entities/ci/runner_details.rb
@@ -9,7 +9,11 @@ class RunnerDetails < Runner
         expose :locked
         expose :maximum_timeout
         expose :access_level
-        expose :version, :revision, :platform, :architecture
+        # TODO: remove in v5 https://gitlab.com/gitlab-org/gitlab/-/issues/415159
+        expose(:version) { |_runner, _options| '' }
+        expose(:revision) { |_runner, _options| '' }
+        expose(:platform) { |_runner, _options| '' }
+        expose(:architecture) { |_runner, _options| '' }
         expose :contacted_at
         expose :maintenance_note