async_cluster: add pipeline support

[utkarshgupta137]

Pull Request check-list

• Does $ tox pass with this change (including linting)?
• Do the CI tests pass with this change (enable it first in your forked repo and wait for the github action build to finish)?
• Is the new or changed code fully tested?
• Is a documentation update included (if this change modifies existing APIs, or introduces new ones)?
• Is there an example added to the examples folder (if applicable)?
• Was the change added to CHANGES file?

Description of change

Closes #2186

[codecov-commenter]

Codecov Report

Merging #2199 (59c5bd0) into master (c54dfa4) will increase coverage by 0.15%.
The diff coverage is 96.19%.

@@ Coverage Diff @@ ## master #2199 +/- ## ========================================== + Coverage 91.88% 92.03% +0.15%  ========================================== Files 108 108 Lines 27389 27629 +240 ========================================== + Hits 25166 25429 +263  + Misses 2223 2200 -23 

Impacted Files	Coverage Δ
redis/asyncio/cluster.py	90.08% <93.89%> (+0.83%)	⬆️
tests/test_asyncio/test_cluster.py	97.64% <97.97%> (+0.42%)	⬆️
redis/cluster.py	90.00% <100.00%> (-0.35%)	⬇️
tests/test_asyncio/test_pipeline.py	100.00% <100.00%> (ø)
tests/test_commands.py	89.92% <0.00%> (+0.12%)	⬆️
redis/asyncio/client.py	92.85% <0.00%> (+0.17%)	⬆️
tests/test_json.py	100.00% <0.00%> (+0.19%)	⬆️
redis/asyncio/connection.py	83.85% <0.00%> (+0.22%)	⬆️
tests/test_asyncio/test_json.py	100.00% <0.00%> (+0.24%)	⬆️
tests/test_cluster.py	97.14% <0.00%> (+0.35%)	⬆️
... and 10 more

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[dvora-h]

@utkarshgupta137 This PR also looks awesome, can you please resolve the conflicts with master so we will can merge it too?