Support topologySpreadConstraints

[brinkenberger]

Currently it is not possible to distribute the deployment in different availability zones (AZ).

Say I have replicas: 3 and three zones:

AZ1: Node1, Node2
AZ2: Node3, Node4
AZ3: Node5, Node6

The following config can currently happen:
Replica 1: Node 1 / AZ1
Replica 2: Node 2 / AZ1
Replica 3: Node 3 / AZ2

I want the scheduler instead to prefer this config:
Replica 1: Node 1 / AZ1
Replica 2: Node 3 / AZ2
Replica 3: Node 5 / AZ3

By supporting topologySpreadConstraints, this is possible.

[orca-security-eu]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Secrets	0   0   0   0	View in Orca

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[antas-marcin]

@brinkenberger welcome! and thank you for your contribution I have a question: is your PR ready for review?

[brinkenberger]

Hey, the PR can be closed. As mentioned in another issue, topologySpreadConstraints is not necessary, just use podAntiAffinity.

If you want to continue on this PR, feel free to do so.