Add separate non-blocking start_app corountine

[Bluenix2]

What do these changes do?

This will add a separate start corountine allowing the user to use a similar half-performant function as run_app but if they wish to do the keepalive sleeps themselves.

Are there changes in behavior for the user?

This has 0 breaking changes, unless someone depends on the previous _run_app function which was renamed to stat_app and had the keepalive code moved.

Related issue number

This should close #5386, which I opened confused about the pre-commit hooks failing.

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
  • 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."

• Unit tests for the changes exist

If there is for run_app then I guess? I did not add any new unit tests for the new start_app function.

The format is <Name> <Surname>.

I do not want to reveal my real name, looking at the document it doesn't seem as if any aliases are there so I am not gonna add myself there. Which is completely fine by me.

Please keep alphabetical order, the file is sorted by names.

Not possible considering run_app is dependent on start_app which means an exception to that rule is made here.

[codecov]

Codecov Report

Merging #5391 (e06168f) into master (9b1792b) will decrease coverage by 0.02%.
The diff coverage is 90.47%.

@@            Coverage Diff             @@
##           master    #5391      +/-   ##
==========================================
- Coverage   97.16%   97.14%   -0.03%     
==========================================
  Files          41       41              
  Lines        8746     8752       +6     
  Branches     1402     1402              
==========================================
+ Hits         8498     8502       +4     
- Misses        129      130       +1     
- Partials      119      120       +1     

Flag	Coverage Δ
unit	97.04% <90.47%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
aiohttp/web.py	97.63% <90.47%> (-1.51%)	⬇️
aiohttp/web_protocol.py	86.12% <0.00%> (-0.29%)	⬇️
aiohttp/client_reqrep.py	97.52% <0.00%> (+0.14%)	⬆️

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[Bluenix2]

Okay, I finally found a nice implementation which passes all unit tests. See #5389 as to why some checks get canceled.

Regarding codecov I am not sure, the code it complains about is just code I simply moved? I also don't have any experience writing any new unit tests if that is needed.

[Rixxan]

I see this PR was closed without being merged - was that intentional and this PR is no longer in development or did this simply slip through the cracks?

[Bluenix2]

I closed this because I was fighting the tests - not exactly sure how I would structure the code to make them pass - and later on re-structured my code to no longer need the added function. I intentionally closed this PR and I am not working on it.