Fix misleading-indentation error for clang

Author: lqf96

include/pybind11/pybind11.h

@@ -477,8 +477,9 @@ class cpp_function : public function {
                 arg.value.dec_ref();
             }
             if (rec->def) {
-                if (rec->def->ml_doc)
+                if (rec->def->ml_doc) {
                     std::free(const_cast<char *>(rec->def->ml_doc));
+                }
                 // Python 3.9.0 decref's these in the wrong order; rec->def
                 // If loaded on 3.9.0, let these leak (use Python 3.9.1 at runtime to fix)
                 // See https://github.com/python/cpython/pull/22670