Don't start motd yum before cloud-init has a chance to start

Some customers with start-up time configuration claim that YUM is "locked".
This is probably because we are discovering what to write in the motd.

Closes: SIM#P12146737

Author: chadmiller-amzn

SOURCES/update-motd.service

@@ -4,6 +4,8 @@ After=network-online.target
 
 [Service]
 Type=oneshot
+TimeoutStartSec=300
+ExecStartPre=-/bin/sleep 240
 ExecStart=/usr/sbin/update-motd
 RemainAfterExit=yes