expose app property for TestClient

[thomaszdxsn]

What do these changes do?

expose app property for TestClient

Are there changes in behavior for the user?

former usage must access test_client.server.app, now is easy, justtest_client.app

Related issue number

#2891

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
• If you provide code modification, please add yourself to CONTRIBUTORS.txt
• Add a new news fragment into the CHANGES folder

[thomaszdxsn]

I don't know why file's changed contain docs/client_reference.rst, no diff obviously

[codecov-io]

Codecov Report

Merging #2901 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2901      +/-   ##
==========================================
+ Coverage   97.98%   97.98%   +<.01%     
==========================================
  Files          40       40              
  Lines        7504     7506       +2     
  Branches     1316     1316              
==========================================
+ Hits         7353     7355       +2     
  Misses         48       48              
  Partials      103      103

Impacted Files	Coverage Δ
aiohttp/test_utils.py	98.85% <100%> (ø)	⬆️

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[asvetlov]

Thanks!

[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