Shipped API files don't include python/binaryninja/py.typed

[meithecatte]

Version and Platform (required):

• Binary Ninja Version: 3.4.4271, also occurs on 3.5.4286-dev (latest dev at time of writing)
• OS: Arch Linux
• CPU Architecture: x64

Bug Description:
Using the type annotations requires manually creating an empty file at python/binaryninja/py.typed, despite the fact that this repo includes such a file.

Steps To Reproduce:

1. Run scripts/install_api.py
2. cd ~/tmp && echo 'import binaryninja' > meow.py && mypy meow.py
3. Observe the following error:

   meow.py:1: error: Skipping analyzing "binaryninja": module is installed, but missing library stubs or py.typed marker  [import]
   meow.py:1: note: See https://mypy.readthedocs.io/en/stable/running_mypy.html#missing-imports
   Found 1 error in 1 file (checked 1 source file)
   

4. Create an empty file at python/binaryninja/py.typed within the binaryninja installation
5. Run mypy meow.py and observe it now works.

Expected Behavior:
mypy works out of the box, with py.typed shipped with the rest of Binary Ninja.

Additional Information:
See also: #2747.

While I can't find it now, I seem to recall seeing an issue where the problem was that empty py.typed files get stripped by the build process, which is why there's now a dummy comment in them. Nonetheless, this doesn't seem to be helping, as they are still not included.

[psifertex]

Good catch, I've modified the cmake config so that should be included in future builds, not just in the repo.