Update net-kourier nightly (#10887)
Update net-kourier nightly (#10887)

bumping knative.dev/net-kourier 60f07fa...7956121:
  > 7956121 upgrade to latest dependencies (# 461)
  > f9c534c set alpn protocols to h2,http/1.1 on downstream tls context (# 442)
  > a562456 Simplify gateway config (# 456)
  > 5253737 upgrade to latest dependencies (# 460)

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