Merge pull request #2473 from murgatroid99/grpc-js_compression_documentation

grpc-js: Update documentation of compression behavior in README

Author: murgatroid99

packages/grpc-js/README.md

@@ -19,7 +19,7 @@ Documentation specifically for the `@grpc/grpc-js` package is currently not avai
 - Servers
 - Streaming
 - Metadata
-- Partial compression support: clients can decompress response messages
+- Partial compression support: clients can compress and decompress messages, and servers can decompress request messages
 - Pick first and round robin load balancing policies
 - Client Interceptors
 - Connection Keepalives