Add priorityClassName configuration to deployment

[LeonoreMangold]

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Developer Done List

• [ ] Tests Added/Updated
• [ ] Updated README.md
• [ ] Verified backward compatible
• [ ] Verified database migrations will not be catastrophic
• [ ] Considered Security, Availability and Confidentiality

For the Reviewer:

By approving this PR, the reviewer acknowledges that they have checked all items in this done list.

Reviewer/Approval Done List

• [ ] Tests Pass Locally
• [ ] CI Build Passes
• [ ] Verified README.md is updated
• [ ] Verified changes are backward compatible
• [ ] Reviewed impact to Security, Availability and Confidentiality (if issue found, add comments and request changes)

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[CLAassistant]

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[LeonoreMangold]

@daniel-spray @AnthonyApptio do you know to whom I can reach out for integration of this PR ? If possible, I would need it as soon as possible as part of an incoming feature in my team. Much thanks !