HyperShift Operator showed panicing logs during e2e runs on different jobs due to a code path that doesn't do a proper nil pointer check. 

Difficult to reproduce, it showed up on e2e-aks.     

 panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x3f5d4d7]

goroutine 1045 [running]:
github.com/openshift/hypershift/hypershift-operator/controllers/hostedcluster/metrics.(*hostedClustersMetricsCollector).Collect(0xc000f03bc0, 0xc000356d20)
	/hypershift/hypershift-operator/controllers/hostedcluster/metrics/metrics.go:492 +0x27b7
github.com/prometheus/client_golang/prometheus.(*Registry).Gather.func1()
	/hypershift/vendor/github.com/prometheus/client_golang/prometheus/registry.go:456 +0x178
created by github.com/prometheus/client_golang/prometheus.(*Registry).Gather in goroutine 1025
	/hypershift/vendor/github.com/prometheus/client_golang/prometheus/registry.go:548 +0xd14   

The panic should never occur.