Remove untested and undocumented interfaces

[judahrand]

What this PR does / why we need it:
This PR removes a bunch of things which no longer seem to be supported in Feast. They result in a bunch of tech debt which makes things harder to push forward. All the things removed were untested.

The documentation to migrate to Feast 0.10+ already exists here and explains that FeatureTables have been replaced with FeatureViews. Uses should have migrated by now.

Which issue(s) this PR fixes:

Fixes #1583

Does this PR introduce a user-facing change?:

Remove `FeatureTables`

[feast-ci-bot]

Hi @judahrand. Thanks for your PR.

I'm waiting for a feast-dev member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[codecov-commenter]

Codecov Report

Merging #2084 (0294315) into master (b5d8a53) will increase coverage by 1.32%.
The diff coverage is 89.47%.

@@            Coverage Diff             @@
##           master    #2084      +/-   ##
==========================================
+ Coverage   83.32%   84.65%   +1.32%     
==========================================
  Files         100       99       -1     
  Lines        8084     7877     -207     
==========================================
- Hits         6736     6668      -68     
+ Misses       1348     1209     -139     

Flag	Coverage Δ
integrationtests	74.84% <89.47%> (+1.08%)	⬆️
unittests	58.75% <84.21%> (+0.56%)	⬆️

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

Impacted Files	Coverage Δ
sdk/python/feast/__init__.py	90.00% <ø> (-0.48%)	⬇️
sdk/python/feast/data_source.py	61.29% <ø> (ø)
sdk/python/feast/errors.py	71.11% <ø> (+1.11%)	⬆️
sdk/python/feast/infra/passthrough_provider.py	100.00% <ø> (ø)
sdk/python/feast/infra/provider.py	92.24% <ø> (+0.51%)	⬆️
sdk/python/feast/registry.py	88.75% <ø> (+8.33%)	⬆️
sdk/python/feast/repo_operations.py	45.26% <33.33%> (+2.68%)	⬆️
sdk/python/feast/feature.py	90.24% <100.00%> (+17.51%)	⬆️
sdk/python/feast/feature_service.py	81.81% <100.00%> (+0.65%)	⬆️
sdk/python/feast/feature_store.py	90.83% <100.00%> (+0.60%)	⬆️
... and 10 more

---

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[woop]

@judahrand the only thing really blocking us from moving forward is the fact that some users have indicated that they do want to have feature table support. The current plan is still to remove feature tables, but I just want to make sure that we aren't missing anything. I think it may be worth discussing it at our next community call and making sure that the community is aware of this change (perhaps by sending out an email on the feast-dev mailing list)

[adchia]

added this to next week's community call agenda

[judahrand]

@adchia @woop Do we think this can be merged subsequent to last week's community call?

[felixwang9817]

hey @judahrand thanks for following up here - Danny and Willem are both on vacation right now, let me try to confirm with them that we're okay to move forward with removing feature tables here

[adchia]

@felixwang9817 The result of our community call was that this was ok. We just need to send out a note to the community (esp to folks like Salesforce) as a heads up.

Thanks for also removing the outdated concepts docs! Removed some tech debt from Gitbook.

/lgtm

[feast-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: adchia, judahrand

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[judahrand]

@adchia I've fixed the conflicts with master. Should be good to go whenever - though #2149 will introduce more conflicts depending on the order of the merges.

[adchia]

/lgtm