Fixed typo in word 'sentinel'

[fuho]

Fixed a typo in word 'sentinel'

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Description of change

Fixed a typo in word 'sentinel' in redis/commands/sentinel.py

[codecov-commenter]

Codecov Report

Merging #2045 (c0370dd) into master (8d949a3) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2045   +/-   ##
=======================================
  Coverage   92.17%   92.17%           
=======================================
  Files         100      100           
  Lines       21024    21024           
=======================================
+ Hits        19378    19379    +1     
+ Misses       1646     1645    -1     

Impacted Files	Coverage Δ
redis/commands/sentinel.py	64.51% <ø> (ø)
tests/test_cluster.py	98.29% <0.00%> (ø)
redis/asyncio/connection.py	82.77% <0.00%> (+0.11%)	⬆️

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[dvora-h]

Thanks for that @fuho