Increase agent's apiserver ready timeout

[brandond]

Increase agent's apiserver ready timeout. Since the agent starts up earlier, the 30 second timeout is causing problems in RKE2 when trying to update K3s for:

• Processes should stop when stopping rke2 process on windows agent rancher/rke2#1755

[mdrahman-suse]

Verified on k3s Master with commit 535a919

Steps

• Create 1 server and 1 agent node (ubuntu 20.04)
• Install k3s using the commit
• Once the nodes and pods are up, use systemctl stop/restart and systemctl stop/start on agent node
• Verify the state changes and the process are in correct state
• Also used killall and uninstall script for validation and ensure that all the process related to k3s is terminated