Use drop_duplicates() instead of groupby (about 1.5~2x faster)

[rightx2]

What this PR does / why we need it:
df.drop_duplicates() is much faster than groupby() + reset_index().

You can test it with the below codes (You can change the number of unique number for each column):

df = pd.DataFrame({
    "a": [np.random.randint(0, 100) for _ in range(1000)],
    "b": [np.random.randint(0, 100) for _ in range(1000)],
    "c": [np.random.randint(0, 100) for _ in range(1000)],
})

%%timeit
df.groupby(['a', 'b']).last().reset_index()

%%timeit
df.drop_duplicates(['a', 'b'], keep="last", ignore_index=True, inplace=True)

Which issue(s) this PR fixes:
No issues related. It's sort of a little performance improvement

Does this PR introduce a user-facing change?:

NONE

[feast-ci-bot]

Hi @rightx2. Thanks for your PR.

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[achals]

/ok-to-test

[codecov-commenter]

Codecov Report

Merging #1617 (ed34cdf) into master (99ee2ce) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1617      +/-   ##
==========================================
- Coverage   83.64%   83.64%   -0.01%     
==========================================
  Files          67       67              
  Lines        5816     5814       -2     
==========================================
- Hits         4865     4863       -2     
  Misses        951      951              

Flag	Coverage Δ
integrationtests	83.55% <100.00%> (-0.01%)	⬇️
unittests	77.84% <100.00%> (-0.01%)	⬇️

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

Impacted Files	Coverage Δ
sdk/python/feast/infra/offline_stores/file.py	96.66% <100.00%> (-0.08%)	⬇️

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[achals]

/retest

[achals]

/lgtm

[achals]

/assign @woop

[achals]

Thanks for the PR @rightx2! I dont have land permissions yet but @woop should be able to get this merged in.

[achals]

/lgtm

[achals]

Probably gotta approve again after being added to the OWNERS file

[feast-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: achals, rightx2

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• OWNERS [achals]

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