Cleanup spec for N+1 environments check on merge requests controller

Clean up Rspec as noted in #29791 (comment 1017711969)

Proposed cleanup diff

diff --git a/spec/controllers/projects/merge_requests_controller_spec.rb b/spec/controllers/projects/merge_requests_controller_spec.rb
index 8ccbc0d3fe2..a943a5e0205 100644
--- a/spec/controllers/projects/merge_requests_controller_spec.rb
+++ b/spec/controllers/projects/merge_requests_controller_spec.rb
@@ -1894,15 +1894,12 @@ def post_assign_issues
         # First run to insert test data from lets, which does take up some 30 queries
         get_ci_environments_status

-        control_count = ActiveRecord::QueryRecorder.new(skip_cached: false) { get_ci_environments_status }.count
+        control_count = ActiveRecord::QueryRecorder.new { get_ci_environments_status }

         environment2 = create(:environment, project: forked)
         create(:deployment, :succeed, environment: environment2, sha: sha, ref: 'master', deployable: build)

-        # TODO address the last 3 queries
-        # See https://gitlab.com/gitlab-org/gitlab-foss/issues/63952 (3 queries)
-        leeway = 3
-        expect { get_ci_environments_status }.not_to exceed_all_query_limit(control_count + leeway)
+        expect { get_ci_environments_status }.not_to exceed_all_query_limit(control_count)
       end
     end