JSON set_file and set_path support

[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)?

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Description of change

Adding the ability to use json.set with a file from disk, or a directory containing multiple json files.

closes #1785

[chayim]

Please see suggestions. It's looking good!

[codecov-commenter]

Codecov Report

Merging #1818 (1757d97) into master (f82ab33) will increase coverage by 0.09%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1818      +/-   ##
==========================================
+ Coverage   94.22%   94.32%   +0.09%     
==========================================
  Files          74       75       +1     
  Lines       15681    15830     +149     
==========================================
+ Hits        14776    14932     +156     
+ Misses        905      898       -7     

Impacted Files	Coverage Δ
redis/commands/json/commands.py	88.88% <100.00%> (+2.02%)	⬆️
tests/test_json.py	100.00% <100.00%> (ø)
redis/__init__.py	90.47% <0.00%> (-9.53%)	⬇️
tests/conftest.py	91.13% <0.00%> (-0.75%)	⬇️
tests/test_search.py	98.78% <0.00%> (-0.25%)	⬇️
setup.py	0.00% <0.00%> (ø)
tests/test_ssl.py	91.66% <0.00%> (ø)
tests/test_commands.py	99.38% <0.00%> (+<0.01%)	⬆️
redis/commands/core.py	90.09% <0.00%> (+0.07%)	⬆️
redis/client.py	89.96% <0.00%> (+0.11%)	⬆️
... and 4 more

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