Add support for CLUSTER ADDSLOTSRANGE

[dvora-h]

Pull Request check-list

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• 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?

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afterwards / while the PR is open.

Description of change

Please provide a description of the change here.
closes #1802

[codecov-commenter]

Codecov Report

Merging #2017 (3ee7c64) into master (4a714aa) will decrease coverage by 0.47%.
The diff coverage is 57.14%.

@@            Coverage Diff             @@
##           master    #2017      +/-   ##
==========================================
- Coverage   92.63%   92.16%   -0.48%     
==========================================
  Files         100      100              
  Lines       20909    21005      +96     
==========================================
- Hits        19369    19359      -10     
- Misses       1540     1646     +106     

Impacted Files	Coverage Δ
redis/client.py	89.39% <ø> (ø)
redis/cluster.py	91.93% <ø> (-0.58%)	⬇️
tests/test_cluster.py	98.23% <40.00%> (-0.06%)	⬇️
redis/commands/cluster.py	94.11% <100.00%> (-0.71%)	⬇️
tests/test_function.py	25.30% <0.00%> (-74.70%)	⬇️
redis/commands/timeseries/__init__.py	94.73% <0.00%> (-5.27%)	⬇️
redis/commands/json/__init__.py	97.56% <0.00%> (-2.44%)	⬇️
redis/commands/parser.py	88.40% <0.00%> (-1.92%)	⬇️
redis/commands/core.py	85.86% <0.00%> (-1.36%)	⬇️
... and 11 more

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