Use IAP for GKE autopilot kubectl access without using the current bastion/jump-box approach - Scrum 20240124

Investigate option proposed by Dave
pending...
current
https://cloud.google.com/kubernetes-engine/docs/tutorials/private-cluster-bastion
proposed
https://cloud.google.com/iap/docs/managing-access

labs
https://www.cloudskillsboost.google/focuses/5561?catalog_rank=%7B%22rank%22%3A2%2C%22num_filters%22%3A0%2C%22has_search%22%3Atrue%7D&parent=catalog&search_id=29584730
https://www.cloudskillsboost.google/focuses/20227?catalog_rank=%7B%22rank%22%3A1%2C%22num_filters%22%3A0%2C%22has_search%22%3Atrue%7D&parent=catalog&search_id=29584730

for example check headers
```
user_email = request.headers.get('X-Goog-Authenticated-User-Email')
user_id = request.headers.get('X-Goog-Authenticated-User-ID')
```