rust-cpython: remove invalid __package__ attribute

Since mercurial.rustext is a package, its __package__ should be, if set,
"mercurial.rustext". AFAIK, we don't have to set this attribute manually
as the rustext module will be imported by the system importer.

https://stackoverflow.com/a/21233334/10435339

rust/hg-cpython/src/lib.rs

@@ -1,42 +1,41 b''
 // lib.rs
 //
 // Copyright 2018 Georges Racinet <[e-mail]>
 //
 // This software may be used and distributed according to the terms of the
 // GNU General Public License version 2 or any later version.
 
 //! Python bindings of `hg-core` objects using the `cpython` crate.
 //! Once compiled, the resulting single shared library object can be placed in
 //! the `mercurial` package directly as `rustext.so` or `rustext.dll`.
 //! It holds several modules, so that from the point of view of Python,
 //! it behaves as the `cext` package.
 //!
 //! Example:
 //! ```
 //! >>> from mercurial.rustext import ancestor
 //! >>> ancestor.__doc__
 //! 'Generic DAG ancestor algorithms - Rust implementation'
 //! ```
 
 #[macro_use]
 extern crate cpython;
 extern crate hg;
 extern crate libc;
 
 mod ancestors;
 mod cindex;
 mod exceptions;
 
 py_module_initializer!(rustext, initrustext, PyInit_rustext, |py, m| {
     m.add(
         py,
         "__doc__",
         "Mercurial core concepts - Rust implementation",
     )?;
 
     let dotted_name: String = m.get(py, "__name__")?.extract(py)?;
-    m.add(py, "__package__", "mercurial")?;
     m.add(py, "ancestor", ancestors::init_module(py, &dotted_name)?)?;
     m.add(py, "GraphError", py.get_type::<exceptions::GraphError>())?;
     Ok(())
 });