Add time series regression to LightGBMRegressor supported problem types

[freddyaboulton]

Pull Request Description

Fixes #2760

Performance tests here: https://alteryx.atlassian.net/wiki/spaces/PS/pages/1046872126/Adding+LightGBM+regressor+to+time+series+estimators+used+in+AutoMLSearch

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After creating the pull request: in order to pass the release_notes_updated check you will need to update the "Future Release" section of docs/source/release_notes.rst to include this pull request by adding :pr:123.

[codecov]

Codecov Report

Merging #2793 (18a0689) into main (916f797) will increase coverage by 0.1%.
The diff coverage is 100.0%.

❗ Current head 18a0689 differs from pull request most recent head 38cb89c. Consider uploading reports for the commit 38cb89c to get more accurate results

@@           Coverage Diff           @@
##            main   #2793     +/-   ##
=======================================
+ Coverage   99.8%   99.8%   +0.1%     
=======================================
  Files        297     298      +1     
  Lines      27718   27731     +13     
=======================================
+ Hits       27650   27663     +13     
  Misses        68      68             

Impacted Files	Coverage Δ
...onents/estimators/regressors/lightgbm_regressor.py	100.0% <100.0%> (ø)
...valml/tests/component_tests/test_lgbm_regressor.py	100.0% <100.0%> (ø)
evalml/data_checks/__init__.py	100.0% <0.0%> (ø)
evalml/tests/data_checks_tests/test_data_checks.py	100.0% <0.0%> (ø)
...valml/tests/pipeline_tests/test_component_graph.py	100.0% <0.0%> (ø)
evalml/data_checks/utils.py	100.0% <0.0%> (ø)

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[jeremyliweishih]

👏

[angela97lin]

LGTM! 👍