py-astroid: updated to 2.5

What's New in astroid 2.5?

* Adds `attr_fset` in the `PropertyModel` class.
* Remove support for Python 3.5.
* Remove the runtime dependency on ``six``. The ``six`` brain remains in
  astroid.
* Enrich the ``brain_collection`` module so that ``__class_getitem__`` method is added to `deque` for
  ``python`` version above 3.9.
* The ``context.path`` is now a ``dict`` and the ``context.push`` method
  returns ``True`` if the node has been visited a certain amount of times.
* Adds a brain for type object so that it is possible to write `type[int]` in annotation.
* Add ``__class_getitem__`` method to ``subprocess.Popen`` brain under Python 3.9 so that it is seen as subscriptable by pylint.
* Adds `degrees`, `radians`, which are `numpy ufunc` functions, in the `numpy` brain. Adds `random` function in the `numpy.random` brain.
* Fix deprecated importlib methods
* Fix a crash in inference caused by `Uninferable` container elements
* Add `python 3.9` support.
* The flat attribute of ``numpy.ndarray`` is now inferred as an ``numpy.ndarray`` itself.
  It should be a ``numpy.flatiter`` instance, but this class is not yet available in the numpy brain.
* Fix a bug for dunder methods inference of function objects
* Fixes a bug in the signature of the ``ndarray.__or__`` method,
  in the ``brain_numpy_ndarray.py`` module.
* Fixes a to-list cast bug in ``starred_assigned_stmts`` method,
  in the ``protocols.py` module.
* Added a brain for ``hypothesis.strategies.composite``
* The transpose of a ``numpy.ndarray`` is also a ``numpy.ndarray``
* Added a brain for ``sqlalchemy.orm.session``
* Separate string and bytes classes patching
* Prevent recursion error for self referential length calls
* Added missing methods to the brain for ``mechanize``, to fix pylint false positives
* Added more supported parameters to ``subprocess.check_output``
* Fix recursion errors with pandas
* Added exception inference for `UnicodeDecodeError`
* `FunctionDef.is_generator` properly handles `yield` nodes in `If` tests
* Fixed exception-chaining error messages.
* Fix failure to infer base class type with multiple inheritance and qualified names
* Fix interpretation of ``six.with_metaclass`` class definitions.
* Reduce memory usage of astroid's module cache.
* Remove dependency on `imp`.
* Do not crash when encountering starred assignments in enums.
* Fix a crash in functools.partial inference when the arguments cannot be determined
* Fix a crash caused by a lookup of a monkey-patched method
* ``is_generator`` correctly considers `Yield` nodes in `AugAssign` nodes
  This fixes a false positive with the `assignment-from-no-return` pylint check.
* Corrected the parent of function type comment nodes.
  These nodes used to be parented to their original ast.FunctionDef parent
  but are now correctly parented to their astroid.FunctionDef parent.

(adam)