Revert "feat(KFLUXVNGD-197): Add HypershiftAWSQuotaAlmostFull alerting rule"

[amisstea]

Reverts #469

I discovered the quota isn't being enforced as I expected (it's actually namespaced, not cluster-scoped). Reverting for now.

[amisstea]

On second thought, this can still be enforced with a ClusterResourceQuota so I'll make those changes instead.

[amisstea]

According to the OCP docs, ClusterResourceQuotas must define a selector that should match active namespaces to the order of dozens at most. The namespaces will contend on this quota during object creation so it can create a performance bottleneck. We must plan to scale into the hundreds of active namespaces at a minimum so this might cause problems for us.

With no great option for enforcing a global quota I'm back to the point where reverting this alerting rule is probably the best option. @mftb @mike-kingsbury please review.

[mike-kingsbury]

/lgtm
/approve