Merge branch 'fix-flaky-mixins-specs' into 'master'

Fix flaky mixins

Closes #34340

See merge request gitlab-org/gitlab!18758

spec/lib/gitlab/cluster/mixins/puma_cluster_spec.rb

@@ -40,7 +40,10 @@ describe Gitlab::Cluster::Mixins::PumaCluster do
 
         yield(process.pid)
       ensure
-        Process.kill(:KILL, process.pid) unless process.eof?
+        begin
+          Process.kill(:KILL, process.pid)
+        rescue Errno::ESRCH
+        end
       end
     end
   end

spec/lib/gitlab/cluster/mixins/unicorn_http_server_spec.rb

@@ -54,7 +54,10 @@ describe Gitlab::Cluster::Mixins::UnicornHttpServer do
 
         yield(process.pid)
       ensure
-        Process.kill(:KILL, process.pid) unless process.eof?
+        begin
+          Process.kill(:KILL, process.pid)
+        rescue Errno::ESRCH
+        end
       end
     end
   end