Redeploy buttons are inaccessible when a stack is locked, even in emergency mode.

[ajshepley]

Sometimes, redeploying the latest deploy may be used to fix an issue. This can happen in systems where there is more than one deployment process available, or when/where more direct surgery and deployments may occur.

Simultaneously, we prevent users from deploying changes while a stack is locked. We offer Emergency Mode, which lets users do deploys when there is a lock, and may emit separate hooks when such operations occur.

However, this does not seem to work for Redeploys, which remain disabled even in emergency mode:

You can manually enable the button to proceed, or visit the Deploy controller URL if you are already familiar.

I think we should enable the Redeploy button in emergency mode.

[ajshepley]

cc: @gigr