Fix StreamResponse equality

[NotSqrt]

What do these changes do?

StreamResponse as subclass of MutableMapping introduced equality defined as return dict(self.items()) == dict(other.items()).
Now, it is back to identity of addresses.

Are there changes in behavior for the user?

Back to the behaviour of pre-3.0 aiohttp version.

Related issue number

Fixes #3100

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes (no specific mention of __eq__ in the docs)
• If you provide code modification, please add yourself to CONTRIBUTORS.txt
  • The format is <Name> <Surname>.
  • Please keep alphabetical order, the file is sorted by names.
• Add a new news fragment into the CHANGES folder
  • name it <issue_id>.<type> for example (588.bugfix)
  • if you don't have an issue_id change it to the pr id after creating the pr
  • ensure type is one of the following:
    • .feature: Signifying a new feature.
    • .bugfix: Signifying a bug fix.
    • .doc: Signifying a documentation improvement.
    • .removal: Signifying a deprecation or removal of public API.
    • .misc: A ticket has been closed, but it is not of interest to users.
  • Make sure to use full sentences with correct case and punctuation, for example: "Fix issue with non-ascii contents in doctest text files."

[codecov-io]

Codecov Report

Merging #3107 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3107      +/-   ##
==========================================
+ Coverage   98.05%   98.06%   +<.01%     
==========================================
  Files          43       43              
  Lines        7834     7836       +2     
  Branches     1353     1353              
==========================================
+ Hits         7682     7684       +2     
  Misses         56       56              
  Partials       96       96

Impacted Files	Coverage Δ
aiohttp/web_response.py	98.19% <100%> (ø)	⬆️

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[asvetlov]

Perfect!

[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