Add anti-affinity rules to controller's replicas

[jkhelil]

As part of the HA setup, we want to add anti-affinity rules to our deployment to make sure replicas do not end up in the same node.

Changes

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• Has Docs included if any changes are user facing
• Has Tests included if any functionality added or changed
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Release Notes

As part of improving high availability (HA) for the Tekton Chains controller, this update adds a preferredDuringSchedulingIgnoredDuringExecution pod anti-affinity rule. This ensures that multiple replicas of the controller are preferably scheduled on different nodes, reducing the risk of service disruption in case of a node failure.

[jkhelil]

/retest

[jkhelil]

/retest

[jkhelil]

/retest

[jkhelil]

/test all

[PuneetPunamiya]

/approve

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: PuneetPunamiya

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[PuneetPunamiya]

/lgtm