[3.6] Fixes #3852 - aiohttp.test_utils.TestClient should return a _RequestContextManager (#3989)

[asvetlov]

(cherry picked from commit a2a9d0a)

Co-authored-by: Bryan Kok Transfusion@users.noreply.github.com

[codecov-io]

Codecov Report

Merging #4022 into 3.6 will increase coverage by 0.05%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##              3.6    #4022      +/-   ##
==========================================
+ Coverage   97.93%   97.99%   +0.05%     
==========================================
  Files          44       44              
  Lines        8820     8823       +3     
  Branches     1385     1386       +1     
==========================================
+ Hits         8638     8646       +8     
+ Misses         77       71       -6     
- Partials      105      106       +1

Impacted Files	Coverage Δ
aiohttp/test_utils.py	99.36% <100%> (ø)	⬆️
aiohttp/streams.py	98.2% <0%> (+0.26%)	⬆️
aiohttp/helpers.py	96.74% <0%> (+0.5%)	⬆️
aiohttp/locks.py	100% <0%> (+7.14%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 57c8c78...6ed27b8. Read the comment docs.