Update status for annotation alpha.istio.io/canonical-serviceaccounts

[nmittler]

This comes from https://github.com/istio/api/pull/1723/files#r516404010. Currently listed as Alpha, is that correct?

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Expected behavior

Steps to reproduce the bug

Version (include the output of istioctl version --remote and kubectl version)

How was Istio installed?

Environment where bug was observed (cloud vendor, OS, etc)

[howardjohn]

It does nothing in the code, and I don't think its intended to do anything. I think its safe to remove @costinm @liminw

[nmittler]

Ping @costinm @liminw

[howardjohn]

removed

[howardjohn]

removed