Update examples/plugin.rs

Co-Authored-By: MarkMcCaskey <MarkMcCaskey@users.noreply.github.com>

examples/plugin.rs

@@ -26,6 +26,7 @@ fn main() {
 
     // get a reference to the function "plugin_entrypoint" which takes an i32 and returns an i32
     let entry_point = instance.func::<(i32), i32>("plugin_entrypoint").unwrap();
+    // call the "entry_point" function in WebAssembly with the number "2" as the i32 argument
     let result = entry_point.call(2).expect("failed to execute plugin");
     println!("result: {}", result);
 }