Wait for agent state before updating helm charts

[dimbleby]

As discussed, a sort-of fix for https://msazure.visualstudio.com/AzureArcPlatform/_workitems/edit/29816874

Not sure about some of the choices here, please consider

• is it right to save throwing the exception to the end, or should we give up before updating the helm chart?
• should we re-check the agent state after helm chart update anyway?
• should we do the same re-ordering in connect as well as update?

And if we like this then we should expect to want to make the same change to the powershell CLI