fix(github-release): update fluxcd/flux2 to v2.0.0-rc.4 (#756)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Devin Buhl <onedr0p@users.noreply.github.com>

kubernetes/bootstrap/kustomization.yaml

@@ -4,7 +4,7 @@
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
-  - github.com/fluxcd/flux2/manifests/install?ref=v2.0.0-rc.3
+  - github.com/fluxcd/flux2/manifests/install?ref=v2.0.0-rc.4
 patches:
   # Remove the network policies that does not work with k3s
   - patch: |-