docs: Small optimization for protodoc (#18179)
docs: Small optimization for protodoc (#18179)

this is a small optimization that removes non-envoy rst files from the output depset of protodoc

this makes the api tarball smaller and allows the downstream code to not have to filter these out

Signed-off-by: Ryan Northey <ea3cd978650417470535f3a4725b6b5042a6ab59@synca.io>
envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy,lyft/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,lyft/envoy