chore: requeue on update conflict

[ChunyiLyu]

Context

follow up from #253

Requeue when update fails with a conflict error instead of returning the error to reduce the occurence of update conflict error "the object has been modified"

2024-10-11T14:08:10Z	ERROR	Reconciler error	{"controller": "promise", "controllerGroup": "platform.kratix.io", "controllerKind": "Promise", "Promise": {"name":"bashb398b"}, "namespace": "", "name": "bashb398b", "reconcileID": "f067966e-ef3a-4ce8-b42b-939ec8cc6f01", "error": "Operation cannot be fulfilled on promises.platform.kratix.io \"bashb398b\": the object has been modified; please apply your changes to the latest version and try again"}
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler
	/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:324
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem
	/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:261
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2
	/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:222

Before this PR, running system tests will produce about 60 of these errors:

k logs -n kratix-platform-system kratix-platform-controller-manager-5c86979644-pw4gt | grep "the object has been modified" | wc
Defaulted container "manager" out of: manager, kube-rbac-proxy
      60    2308   27173

With this PR:

❯ k -n kratix-platform-system logs kratix-platform-controller-manager-5c86979644-pcmmp| grep "the object has been modified" | wc
Defaulted container "manager" out of: manager, kube-rbac-proxy
      11     444    5246