THRIFT-4960 bare trait (dyn) warnings
Client: Rust
Patch: Danny Browning

This closes #1851
diff --git a/lib/rs/src/server/mod.rs b/lib/rs/src/server/mod.rs
index 3d42891..b719d1b 100644
--- a/lib/rs/src/server/mod.rs
+++ b/lib/rs/src/server/mod.rs
@@ -91,7 +91,7 @@
     /// the response to `o`.
     ///
     /// Returns `()` if the handler was executed; `Err` otherwise.
-    fn process(&self, i: &mut TInputProtocol, o: &mut TOutputProtocol) -> ::Result<()>;
+    fn process(&self, i: &mut dyn TInputProtocol, o: &mut dyn TOutputProtocol) -> ::Result<()>;
 }
 
 /// Convenience function used in generated `TProcessor` implementations to
@@ -99,7 +99,7 @@
 pub fn handle_process_result(
     msg_ident: &TMessageIdentifier,
     res: ::Result<()>,
-    o_prot: &mut TOutputProtocol,
+    o_prot: &mut dyn TOutputProtocol,
 ) -> ::Result<()> {
     if let Err(e) = res {
         let e = match e {