fix tests including dead code warnings

Author: TaKO8Ki

tests/client.rs

@@ -45,7 +45,7 @@ fn client_test_infer_bin() {
     let diag = rls.wait_for_diagnostics();
 
     assert!(diag.uri.as_str().ends_with("src/main.rs"));
-    assert!(diag.diagnostics[0].message.contains("struct is never constructed: `UnusedBin`"));
+    assert!(diag.diagnostics[0].message.contains("struct `UnusedBin` is never constructed"));
 }
 
 #[test]
@@ -59,7 +59,7 @@ fn client_test_infer_lib() {
     let diag = rls.wait_for_diagnostics();
 
     assert!(diag.uri.as_str().ends_with("src/lib.rs"));
-    assert!(diag.diagnostics[0].message.contains("struct is never constructed: `UnusedLib`"));
+    assert!(diag.diagnostics[0].message.contains("struct `UnusedLib` is never constructed"));
 }
 
 #[test]