Get safely request argument

[pcrespov]

Problem

aiohttp-security decorators fail when router calls the handles using key-arguments instead of positional arguments.

In particular, this happens with the router class in aiohttp_apiset/swagger

  File "/home/devp/osparc-simcore/.venv/lib/python3.6/site-packages/aiohttp_session/__init__.py", line 149, in factory
    response = await handler(request)
  File "/home/devp/osparc-simcore/.venv/lib/python3.6/site-packages/aiohttp_apiset/middlewares.py", line 96, in process
    response = await handler(request)
  File "/home/devp/osparc-simcore/services/web/server/src/simcore_service_webserver/rest/middlewares.py", line 12, in handle_errors
    response = await handler(request)
  File "/home/devp/osparc-simcore/.venv/lib/python3.6/site-packages/aiohttp_apiset/swagger/route.py", line 90, in handler
    response = await self._handler(**parameters)
  File "/home/devp/osparc-simcore/.venv/lib/python3.6/site-packages/aiohttp_security/api.py", line 136, in wrapped
    request = args[-1]

Propose

safe check of request argument prioritizing key over positional arguments

[codecov]

Codecov Report

Merging #186 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #186   +/-   ##
=======================================
  Coverage   94.75%   94.75%           
=======================================
  Files          12       12           
  Lines         591      591           
  Branches       21       21           
=======================================
  Hits          560      560           
  Misses         24       24           
  Partials        7        7

Impacted Files	Coverage Δ
aiohttp_security/api.py	90.24% <100%> (ø)	⬆️

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[asvetlov]

Thank you for PR.
Unfortunately, I've chosen another solution: no more decorators but check_permission explicit call.