v1.14.4

Fixes

• Static upstream support for setting proxy protocol https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/transport_sockets/http_11_proxy/v3/upstream_http_11_connect.proto.html (solo-io/solo-projects#4760)
• Changed the static upstream useTls field from a bool to google.protobuf.BoolValue, to allow explicitly disabling TLS autodetection based on port. (solo-io/solo-projects#4795)
• Expose the access log flush duration option in Envoy to enable flushing to the access log on a periodic basis. The default behaviour is to only write to the access log when a connection is closed meaning that long-running tcp connections may take a long time to get written to the access log. (solo-io/solo-projects#4895)
• Updates glooctl check to use the GPRC endpoint for proxy validation.
  This fixes an issue where the check would report false-positives
  for invalid proxies that were not persisted. (#7697)
• Backport change to support mismatched versions of the gRPC transcoding API to make upgrade/migration without downtime possible. (#8080)