remove obsolete HeapStatData comment about RawStatData (#6849)
remove obsolete HeapStatData comment about RawStatData (#6849)

Signed-off-by: Fred Douglas <4b7c0f16d6df8491ab57e52f3bc89464fb1ef2c5@google.com>
envoyproxy/envoy-wasm,istio/envoy,lyft/envoy,lizan/envoy,jrajahalme/envoy,lyft/envoy,istio/envoy,jrajahalme/envoy,jrajahalme/envoy,eklitzke/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,envoyproxy/envoy-wasm,lyft/envoy,envoyproxy/envoy-wasm,lizan/envoy,jrajahalme/envoy,eklitzke/envoy,envoyproxy/envoy,lyft/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,lizan/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,istio/envoy,istio/envoy,lyft/envoy,lizan/envoy,istio/envoy,eklitzke/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,eklitzke/envoy,jrajahalme/envoy,jrajahalme/envoy,envoyproxy/envoy-wasm,eklitzke/envoy,istio/envoy,eklitzke/envoy,lyft/envoy,lizan/envoy,istio/envoy,lizan/envoy,envoyproxy/envoy