Bunch of CVEs are fixed in go v1.19.6 that require us to bump - latest patch releases are built with Go1.15 so we should bump

See changes - https://github.com/golang/go/issues?q=milestone%3AGo1.19.6+label%3ACherryPickApproved

• knative/serving
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 #13748
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 #13749
• knative-sandbox/net-istio
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6  knative-extensions/net-istio#1071
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-istio#1072
• knative-sandbox/net-contour
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 knative-extensions/net-contour#882
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-contour#883
• knative-sandbox/net-gateway-api
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 knative-extensions/net-gateway-api#458
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-gateway-api#459
• knative-sandbox/net-kourier
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 knative-extensions/net-kourier#1006
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-kourier#1007
• knative-sandbox/net-certmanager
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 knative-extensions/net-certmanager#501
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-certmanager#502
• knative-sandbox/net-http01
  • release-1.8 - [release-1.8] trigger to build release with go1.19.6 knative-extensions/net-http01#469
  • release-1.9 - [release-1.9] trigger to build release with go1.19.6 knative-extensions/net-http01#470