Modify the skaffold v2 render prompt behavior

[yuwenma]

Per offline discussion with @briandealwis , this is what we believe the appropriate behavior when prompting a message in render.

• if the hydration dir exists and is empty => no prompt
• if the hydration dir exists and there is content but no Kptfile => exit: this doesn't look right
• if the hydration dir exists and there is content and Kptfile => prompt to remove ?

[yuwenma]

cc @briandealwis

[tejal29]

Render prompt will not feasible in cloud deploy scenario as well as cloud code. Closing this for now.

[tejal29]

closing this as dupe of #7608