Add s3 support (with custom endpoints)

[woop]

What this PR does / why we need it:

Refactored #1549 to work with the new test suite. Also added support for testing S3 using Minio.

Added @qooba as co-author.

Which issue(s) this PR fixes:

Fixes #1548

Does this PR introduce a user-facing change?:

Added support for S3 as well as S3 with custom endpoints

[codecov-commenter]

Codecov Report

Merging #1789 (5986998) into master (da436b5) will decrease coverage by 21.44%.
The diff coverage is 55.81%.

@@             Coverage Diff             @@
##           master    #1789       +/-   ##
===========================================
- Coverage   85.37%   63.92%   -21.45%     
===========================================
  Files          88       89        +1     
  Lines        6583     6700      +117     
===========================================
- Hits         5620     4283     -1337     
- Misses        963     2417     +1454     

Flag	Coverage Δ
integrationtests	?
unittests	63.92% <55.81%> (+0.37%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...tegration/feature_repos/test_repo_configuration.py	68.02% <0.00%> (-31.98%)	⬇️
...tegration/feature_repos/universal/feature_views.py	63.63% <ø> (-36.37%)	⬇️
...tegration/offline_store/test_s3_custom_endpoint.py	25.00% <25.00%> (ø)
...k/python/feast/infra/offline_stores/file_source.py	85.05% <83.33%> (-0.86%)	⬇️
sdk/python/feast/infra/offline_stores/file.py	97.14% <100.00%> (+0.05%)	⬆️
...ion/feature_repos/universal/data_source_creator.py	77.77% <100.00%> (ø)
.../integration/online_store/test_universal_online.py	16.32% <0.00%> (-83.68%)	⬇️
.../integration/online_store/test_online_retrieval.py	17.39% <0.00%> (-82.61%)	⬇️
sdk/python/tests/utils/online_read_write_test.py	18.18% <0.00%> (-81.82%)	⬇️
...fline_store/test_universal_historical_retrieval.py	20.25% <0.00%> (-79.75%)	⬇️
... and 46 more

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[woop]

Can't really get around hardcoding access_key and secret in two places right now. The test suite doesn't allow us to inject configuration. cc @achals it would be nice if we could propagate a config (context-like) object.

[achals]

Agreed yeah I'll make a task for that

[achals]

/lgtm

[achals]

nit, type annotations for the output of this method?

[achals]

Agreed yeah I'll make a task for that

[feast-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: achals, woop

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• OWNERS [achals,woop]

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[feast-ci-bot]

New changes are detected. LGTM label has been removed.