gh-143672: Finish conversion of the struct module to Argument Clinic (GH-143857)

Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>

Author: serhiy-storchaka

Lib/test/test_inspect/test_inspect.py

@@ -6266,6 +6266,10 @@ def test_stat_module_has_signatures(self):
         import stat
         self._test_module_has_signatures(stat)
 
+    def test_struct_module_has_signatures(self):
+        import struct
+        self._test_module_has_signatures(struct)
+
     def test_string_module_has_signatures(self):
         import string
         self._test_module_has_signatures(string)