Add missing permission for 'tiers' resources

[sebhoss]

Description

Allows calico-apiserver to handle tier resources.

Related issues/PRs

fixes #9481

Todos

• [ ] Tests
• [ ] Documentation
• [ ] Release note

Release Note

Add permission to Calico API server to create tier resources.

Reminder for the reviewer

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[sebhoss]

wrt. testing: We are using conftest in our team to verify that k8s manifests have certain properties, e.g. in order to verify this change here, I've added the following to our internal test:

package main

import rego.v1

deny contains msg if {
    some resource in input

    role := resource.contents
    role.apiVersion == "rbac.authorization.k8s.io/v1"
    role.kind == "ClusterRole"
    role.metadata.name == "calico-crds"

    rules := [rule |
        some rule in role.rules
        rule.apiGroups == ["crd.projectcalico.org"]
        rule.resources[_] == "tiers"
        rule.verbs[_] == "create"
    ]

    count(rules) == 0

    msg := sprintf("ClusterRole '%v' does not allow to create tiers", [role.metadata.name])
}

This test is executed every time someone changes our internal copy of the calico-apiserver manifests and ensures that the missing permission is not missing :sweat_smile:

[mazdakn]

/sem-approve