Revert "bpo-23689: re module, fix memory leak when a match is terminated by a signal or memory allocation failure (GH-32283)"
This reverts commit 6e3eee5c11.
Manual fixups to increase the MAGIC number and to handle conflicts with
a couple of changes that landed after that.
Thanks for reviews by Ma Lin and Serhiy Storchaka.
It combines PyImport_ImportModule() and PyObject_GetAttrString()
and saves 4-6 lines of code on every use.
Add also _PyImport_GetModuleAttr() which takes Python strings as arguments.