FIX: Remove HEAD -> GET request swap workaround

[vcastane]

Description

Remove a workaround replacing HEAD requests with GET requests for async requests.
This workaround is no longer needed after the underlying bug was fixed in aio-libs/aiohttp#5012

Issues Resolved

Partially resolves #698
The rest of the issue is user (my) error.

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[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 72.16%. Comparing base (bd91530) to head (9560795).
Report is 52 commits behind head on main.

Files	Patch %	Lines
opensearchpy/_async/http_aiohttp.py	50.00%	1 Missing ⚠️
opensearchpy/connection/http_async.py	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #699      +/-   ##
==========================================
+ Coverage   72.14%   72.16%   +0.01%     
==========================================
  Files          89       89              
  Lines        7945     7943       -2     
==========================================
  Hits         5732     5732              
+ Misses       2213     2211       -2     

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[dblock]

Do we need to lock aiohttp >= a certain version as part of the PR?

[dblock]

Should be None? There other other places where we assign things to "" where in fact we mean none I believe, too.

[dblock]

I believe this is no longer needed as we only reuse it once, maybe just check the verb where it's needed?

[dblock]

Is there a way to write a test for this, too? Something that fails without this change?

[saimedhi]

Do we need to lock aiohttp >= a certain version as part of the PR?

• Bug resolved in aiohttp version 3.7.0.
• opensearch-py compatibility: aiohttp>=3,<4.
• I suggest instead of locking aiohttp to >=3.7.0,<4, we should check the aiohttp version and conditionally remove the workaround for aiohttp >=3.7.0.
• Detailed code review required to identify necessary code changes.

[saimedhi]

• I suggest instead of locking aiohttp to >=3.7.0,<4, we should check the aiohttp version and conditionally remove the workaround for aiohttp >=3.7.0.

Disregard the previous comment. To resolve this issue #715 , we're planning to lock aiohttp to >=3.9.2,<4. Thus, simply removing the workaround should suffice."

[saimedhi]

Hello @vcastane ,

Could you please take a look at finishing this PR when you have a moment? If you need any help, let us know.

Thanks a lot!

[dblock]

Finished this in #794.