Re-open Semantic Logger appenders in Cluster mode

This missing config meant Semantic Logger was not working in prod, where
we use Puma in Cluster mode.

See https://logger.rocketjob.io/forking.html#puma

Author: mwtrew

config/puma.rb

@@ -38,6 +38,11 @@
 
   workers worker_count
 
+  before_worker_boot do
+    # Re-open appenders after forking the process
+    SemanticLogger.reopen
+  end
+
   # Use the `preload_app!` method when specifying a `workers` number.
   # This directive tells Puma to first boot the application and load code
   # before forking the application. This takes advantage of Copy On Write
@@ -48,3 +53,5 @@
 
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart
+
+