Merge pull request rails#49971 from composerinteralia/reaper-thread-name

Name the connection pool reaper thread

Author: rafaelfranca

activerecord/lib/active_record/connection_adapters/abstract/connection_pool/reaper.rb

@@ -43,6 +43,7 @@ def spawn_thread(frequency)
                 # Advise multi-threaded app servers to ignore this thread for
                 # the purposes of fork safety warnings
                 Thread.current.thread_variable_set(:fork_safe, true)
+                Thread.current.name = "AR Pool Reaper"
                 running = true
                 while running
                   sleep t