fix: add annotation for UI ingress

[kakascx]

Add the https annotation for UI ingress when using secure mode

I'm using the ingress to expose the adminUI service. It doesn't work under the master branch and return http status 307, meanwhile the location in response header is the requeset address forever

By adding the annotaion nginx.ingress.kubernetes.io/backend-protocol: HTTPS can solve this problem.

[cockroach-teamcity]

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