docs: Fix refs in Lua docs (#12313)
docs: Fix refs in Lua docs (#12313)

This is a docs only change, mostly on how to refer to LuaPerRoute info.

Signed-off-by: Dhi Aurrahman <dio@tetrate.io>

Mirrored from https://github.com/envoyproxy/envoy @ 3dedf1693f45239c670c5ba7598db44ff2e32c2f

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