staging: remove sprayproxy from host clusters

With the completion of KFLUXINFRA-1790[^1], we no longer need sprayproxy
on the host clusters.

Remove it from the staging overlay.

[^1]: https://issues.redhat.com/browse/KFLUXINFRA-1790

Part-of: KFLUXINFRA-2240
Signed-off-by: Andy Sadler <[email protected]>

Author: sadlerap

argo-cd-apps/overlays/konflux-public-staging/delete-applications.yaml

@@ -11,3 +11,9 @@ kind: ApplicationSet
 metadata:
   name: nvme-storage-configurator
 $patch: delete
+---
+apiVersion: argoproj.io/v1alpha1
+kind: ApplicationSet
+metadata:
+  name: sprayproxy
+$patch: delete