Automated test for minimum Kubernetes version

[mpstefan]

Each run of the pipeline should run on the latest version of Kubernetes and 1.23, or minimum Kubernetes version.

To be done on every PR as well.

[ciarams87]

The minimum supported version is now actually 1.23 - the below error occurs when installing the Gateway CRDs on 1.22:

kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v0.8.0/standard-install.yaml

error: error validating "https://github.com/kubernetes-sigs/gateway-api/releases/download/v0.8.0/standard-install.yaml": error validating data: [ValidationError(CustomResourceDefinition.spec.versions[0].schema.openAPIV3Schema.properties.spec.properties.controllerName): unknown field "x-kubernetes-validations" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1.JSONSchemaProps, ValidationError(CustomResourceDefinition.spec.versions[1].schema.openAPIV3Schema.properties.spec.properties.controllerName): unknown field "x-kubernetes-validations" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1.JSONSchemaProps]; if you choose to ignore these errors, turn validation off with --validate=false

[kate-osborn]

The minimum supported version is now actually 1.23 - the below error occurs when installing the Gateway CRDs on 1.22:

kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v0.8.0/standard-install.yaml

error: error validating "https://github.com/kubernetes-sigs/gateway-api/releases/download/v0.8.0/standard-install.yaml": error validating data: [ValidationError(CustomResourceDefinition.spec.versions[0].schema.openAPIV3Schema.properties.spec.properties.controllerName): unknown field "x-kubernetes-validations" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1.JSONSchemaProps, ValidationError(CustomResourceDefinition.spec.versions[1].schema.openAPIV3Schema.properties.spec.properties.controllerName): unknown field "x-kubernetes-validations" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1.JSONSchemaProps]; if you choose to ignore these errors, turn validation off with --validate=false

Ah my bad, I read this blog post incorrectly: https://gateway-api.sigs.k8s.io/blog/2023/0829-mesh-support/#kubernetes-122-and-older. Good catch!