Add nodeSelectors for Akri Agent

[jbpaux]

What this PR does / why we need it:
It adds nodeSelectors on the Agent to ensure the pod is deployed on specific node.
It closes #414

Special notes for your reviewer:

If applicable:

• this PR has an associated PR with documentation in akri-docs
• this PR contains unit tests
• added code adheres to standard Rust formatting (cargo fmt)
• code builds properly (cargo build)
• code is free of common mistakes (cargo clippy)
• all Akri tests succeed (cargo test)
• inline documentation builds (cargo doc)
• all commits pass the DCO bot check by being signed off -- see the failing DCO check for instructions on how to retroactively sign commits

[jbpaux]

/version patch

[kate-goldenring]

Thanks @jbpaux!

Also verified this works selecting for nodename on my cluster with the following:

helm package deployment/helm 
helm install akri akri-0.8.25.tgz --set 'agent.nodeSelectors.kubernetes\.io/hostname=kagold-thinkpad-x1-carbon-6th' --set useLatestContainers=true

[jbpaux]

Hi,
any opinions ? :)

[kate-goldenring]

Hi, any opinions ? :)

Thanks for the bump @jbpaux. This is good to merge -- once we bump the version to 0.8.27

[kate-goldenring]

/version patch

[kate-goldenring]

/version patch