Updating of the metering labels from 7.8 -> 7.9 causes an upgrade failure when upgrading from the 7.8 operator to the 7.9 operator.

{"level":"error","ts":1615812366.717031,"logger":"controller-runtime.controller","msg":"Reconciler error","controller":"apicurito-controller","request":"apicurito/apicurito-service","error":"Apicurito CR changed: UpdateResources : Deployment.apps \"apicurito-service-generator\" is invalid: spec.selector: Invalid value: v1.LabelSelector{MatchLabels:map[string]string

Unknown macro: {"rht.subcomp_t"}

, MatchExpressions:[]v1.LabelSelectorRequirement(nil)}: field is immutable","stacktrace":"github.com/go-logr/zapr.(*zapLogger).Error\n\t/remote-source/app/apicurito/vendor/github.com/go-logr/zapr/zapr.go:128\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler\n\t/remote-source/app/apicurito/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:258\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem\n\t/remote-source/app/apicurito/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:232\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).worker\n\t/remote-source/app/apicurito/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:211\nk8s.io/apimachinery/pkg/util/wait.JitterUntil.func1\n\t/remote-source/app/apicurito/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:152\nk8s.io/apimachinery/pkg/util/wait.JitterUntil\n\t/remote-source/app/apicurito/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:153\nk8s.io/apimachinery/pkg/util/wait.Until\n\t/remote-source/app/apicurito/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:88"}

It would appear that matchLabels are immutable and therefore cannot be edited.

See https://github.com/kubernetes/client-go/issues/508