[xray] Add priority class support

[cheries]

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Is this a BUG REPORT or FEATURE REQUEST? (choose one): Feature

Version of Helm and Kubernetes: k8s: 1.18.9 Helm: 3.1.1

Which chart: stable/xray

What happened: Cannot specify a priority class value in values.yaml and it is required in our cluster.

What you expected to happen: To be able to specify a priority class as we do for the artifactory chart.

[rahulsadanandan]

@cheries Thanks We have created an internal ticket to track this. will plan for this in the upcoming releases.

[rahulsadanandan]

@cheries this is available from 103.42.0 chart versions.