admin: add host weight to cluster json response (#5216)
admin: add host weight to cluster json response (#5216)

This adds the host's weight to the `/clusters?format=json` response.

Signed-off-by: Venil Noronha <veniln@vmware.com>

Mirrored from https://github.com/envoyproxy/envoy @ 9039f24198c35939af411c4102fe64b9aba7d6b1

lyft/envoy-api,lyft/envoy-api,lyft/envoy-api