eks/fargate: truncate stateful set name

[rmfitzpatrick]

If installing with --generate-name the stateful set pod names will be too long for the statefulset.kubernetes.io/pod-name label value and lead to pod creation errors:

statefulset/splunk-otel-collector-1645717371-k8s-cluster-receiver   create Pod splunk-otel-collector-1645717371-k8s-cluster-receiver-0 in StatefulSet splunk-otel-collector-1645717371-k8s-cluster-receiver failed error: Pod "splunk-otel-collector-1645717371-k8s-cluster-receiver-0" is invalid: metadata.labels: Invalid value: "splunk-otel-collector-1645717371-k8s-cluster-receiver-7944b495c4": must be no more than 63 characters

These changes add an even more truncated name for the stateful set.

Appears related to kubernetes/kubernetes#64023, which went stale.