Update Envoy to 6931f18 (#2178)
Update Envoy to 6931f18 (#2178)

Pulls in https://github.com/envoyproxy/envoy/commit/1a66a0ffe2a67634dfe38293ddd2a55215c085cd
which should address the last known blocker to using an arm64 binary of
bazelisk/bazel on macOS.

Signed-off-by: JP Simard <0f41a0b3b760b54df703e860e40fef1c388ed2c5@jpsim.com>
envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile,envoyproxy/envoy-mobile