Update net-istio nightly (#12852)
Update net-istio nightly (#12852)

bumping knative.dev/net-istio 47d7e1a...1bf3eaf:
  > 1bf3eaf Update actions (# 906)
  > 5be2e15 Update community files (# 905)

Signed-off-by: Knative Automation <f415700d4d0ce1c81810fe7553e3eea2bed16231@knative.team>
knative/serving,knative/serving