py-ipython: updated to 7.17.0

IPython 7.17
============

IPython 7.17 brings a couple of new improvements to API and a couple of user
facing changes to make the terminal experience more user friendly.

:ghpull:`12407` introduces the ability to pass extra argument to the IPython
debugger class; this is to help a new project from ``kmaork``
(https://github.com/kmaork/madbg) to feature a fully remote debugger.

:ghpull:`12410` finally remove support for 3.6, while the codebase is still
technically compatible; IPython will not install on Python 3.6.

lots of work on the debugger and hidden frames from ``@impact27`` in
:ghpull:`12437`, :ghpull:`12445`, :ghpull:`12460` and in particular
:ghpull:`12453` which make the debug magic more robust at handling spaces.

Biggest API addition is code transformation which is done before code execution;
IPython allows a number of hooks to catch non-valid Python syntax (magic, prompt
stripping...etc). Transformers are usually called many time; typically:

 - When trying to figure out whether the code is complete and valid (should we
   insert a new line or execute ?)
 - During actual code execution pass before giving the code to Python's
   ``exec``.

This lead to issues when transformer might have had side effects; or do external
queries. Starting with IPython 7.17 you can expect your transformer to be called
less time.

Input transformers are now called only once in the execution path of
`InteractiveShell`, allowing to register transformer that potentially have side
effects (note that this is not recommended). Internal methods `should_run_async`, and
`run_cell_async` now take a recommended optional `transformed_cell`, and
`preprocessing_exc_tuple` parameters that will become mandatory at some point in
the future; that is to say cells need to be explicitly transformed to be valid
Python syntax ahead of trying to run them. :ghpull:`12440`;

``input_transformers`` can now also have an attribute ``has_side_effects`` set
to `True`, when this attribute is present; this  will prevent the transformers
from being ran when IPython is trying to guess whether the user input is
complete. Note that this may means you will need to explicitly execute in some
case where your transformations are now not ran; but will not affect users with
no custom extensions.


(adam)