update prod run script

bin/prod

@@ -10,6 +10,8 @@ export FLASK_ENV=production
 
 mkdir -p $BASE
 
+kill $(cat $BASE/gunicorn.pid) 2>&1
+
 gunicorn \
   --bind 127.0.0.1:4000 "suchwow.app:app" \
   --daemon \
@@ -17,4 +19,4 @@ gunicorn \
   --pid $BASE/gunicorn.pid \
   --reload
 
-echo "Starting gunicorn"
+echo "Starting gunicorn with pid $(cat $BASE/gunicorn.pid)"