Drop await aiohttp.request() syntax for sake of context manager

[asvetlov]

Fixes #2540

[codecov-io]

Codecov Report

Merging #2541 into master will increase coverage by 0.09%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2541      +/-   ##
==========================================
+ Coverage   97.16%   97.26%   +0.09%     
==========================================
  Files          40       40              
  Lines        8193     8147      -46     
  Branches     1441     1440       -1     
==========================================
- Hits         7961     7924      -37     
+ Misses        100       92       -8     
+ Partials      132      131       -1

Impacted Files	Coverage Δ
aiohttp/helpers.py	97.77% <ø> (-0.02%)	⬇️
aiohttp/test_utils.py	98.21% <100%> (ø)	⬆️
aiohttp/web_protocol.py	88.47% <0%> (+0.31%)	⬆️
tests/autobahn/client.py	96.99% <0%> (+1.92%)	⬆️

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[asvetlov]

PR is done.
Will merge it tomorrow if nobody objects.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a [new issue] for related bugs.
If you feel like there's important points made in this discussion, please include those exceprts into that [new issue].
[new issue]: https://github.com/aio-libs/aiohttp/issues/new