Add ResourceQuota for critical pods

[stefanprodan]

Added ResourceQuota for critical pods set to max 1K pods to allow horizontal scaling and sharding.

Fixes insufficient quota error on GKE, reported here.

Tested on GKE 1.26

$ flux check
► checking prerequisites
✔ Kubernetes 1.26.2-gke.1000 >=1.20.6-0
► checking controllers
✔ helm-controller: deployment ready
► ghcr.io/fluxcd/helm-controller:v0.32.2
✔ kustomize-controller: deployment ready
► ghcr.io/fluxcd/kustomize-controller:v1.0.0-rc.2
✔ notification-controller: deployment ready
► ghcr.io/fluxcd/notification-controller:v1.0.0-rc.2
✔ source-controller: deployment ready
► ghcr.io/fluxcd/source-controller:v1.0.0-rc.2
► checking crds
✔ alerts.notification.toolkit.fluxcd.io/v1beta2
✔ buckets.source.toolkit.fluxcd.io/v1beta2
✔ gitrepositories.source.toolkit.fluxcd.io/v1
✔ helmcharts.source.toolkit.fluxcd.io/v1beta2
✔ helmreleases.helm.toolkit.fluxcd.io/v2beta1
✔ helmrepositories.source.toolkit.fluxcd.io/v1beta2
✔ kustomizations.kustomize.toolkit.fluxcd.io/v1
✔ ocirepositories.source.toolkit.fluxcd.io/v1beta2
✔ providers.notification.toolkit.fluxcd.io/v1beta2
✔ receivers.notification.toolkit.fluxcd.io/v1
✔ all checks passed

PS. We need to find a better place for the manifest location, but since this requires changes to the manifest generation logic and packaging, I'll leave it for another time.