Update src/executor.rs

fix executor other than tokio

Co-authored-by: Héctor Ramón <hector0193@gmail.com>

src/executor.rs

@@ -40,8 +40,7 @@ mod platform {
         }
 
         fn enter<R>(&self, f: impl FnOnce() -> R) -> R {
-            let _guard = self.0.enter();
-            f()
+            super::Executor::enter(&self.0, f)
         }
     }
 }