Parallelize `update` integration test suite

[cPu1]

The integration test suite for updating the control plane and nodegroup has the longest runtime (~1h 30m) among all integration test suites. There's room for parallelizing the individual test specs, helping us cut down the runtime.

[github-actions]

This issue is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This issue was closed because it has been stalled for 5 days with no activity.

[github-actions]

This issue is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 5 days.