Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 3.5.2 to 3.5.3.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/3.x/CHANGES)
- [Commits](https://github.com/sphinx-doc/sphinx/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

DOC: Update some plotting code to current Matplotlib idioms

- 3D Axes are created via add_subplot(projection='3d')
- There is now a `stairs()` function that's specifically designed for
  showing histogram curves
- Labels should be passed as keyword arguments to the plot functions
  instead of to `legend()`, which reduces the risk of mixing them up.
- ensure equal axis scaling in the meshgrid example

DOC: add release note for removal of /usr/include from include paths

Follow-up to gh-18658

BLD: remove /usr/include from default include dirs

Including this directory is painful for cross-compiling, see
gh-14980 and gh-13280. Removing this directory fixes the following
build failure:
```
gcc: numpy/core/src/common/numpyos.c
In file included from numpy/core/src/common/numpyos.c:23:
/usr/include/xlocale.h:27:16: error: redefinition of ‘struct __locale_struct’
   27 | typedef struct __locale_struct
```
This error also shows up in various other build issues outside of the
NumPy issue tracker.

Compilers normally always include this path, so this shouldn't break
anything. The default include paths for the compiler can be checked,
e.g. for gcc with `cpp -v`. That will typically have /usr/include last.

In case this breaks something for a nonstandard compiler, that can be
worked around via a site.cfg file in the root of the repo (or
equivalently, `~/numpy-site.cfg`)  containing:
```
[DEFAULT]
include_dirs = /usr/include
```

The same principle should apply to `/usr/lib`. I will make that change
in a separate commit, because the failure mode for that will be
different (and I'm not running into it right now).

MAINT: OrderedDict is no longer necessary from Python 3.7

MAINT: Do not claim input to binops is `self` (array object)

ENH: Use new argument parsing for array creation functions