Add support for PEXPIRETIME

[dvora-h]

Pull Request check-list

Please make sure to review and check all of these items:

• 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)?

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Description of change

closes #1807

[codecov-commenter]

Codecov Report

Merging #1861 (cb5c965) into master (c4e4088) will decrease coverage by 0.02%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #1861      +/-   ##
==========================================
- Coverage   92.21%   92.18%   -0.03%     
==========================================
  Files         100      100              
  Lines       20978    20991      +13     
==========================================
+ Hits        19344    19351       +7     
- Misses       1634     1640       +6     

Impacted Files	Coverage Δ
tests/test_commands.py	99.10% <40.00%> (-0.18%)	⬇️
redis/commands/core.py	85.90% <100.00%> (-0.09%)	⬇️
tests/test_cluster.py	98.29% <0.00%> (ø)
redis/asyncio/connection.py	82.77% <0.00%> (+0.11%)	⬆️

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