Add LightGBM Estimator To AutoML

[bchen1116]

Fix #1093

Adds LightGBM estimator to AutoML Search. Perf test results are in this document

** Note these test results are taken before this commit to remove LightGBM from AutoML; however, I expect the results would be similar to retrieving the results after the removal of LightGBM, as described in the doc.

[codecov]

Codecov Report

Merging #1199 into main will increase coverage by 8.69%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1199      +/-   ##
==========================================
+ Coverage   91.22%   99.92%   +8.69%     
==========================================
  Files         196      196              
  Lines       12006    12007       +1     
==========================================
+ Hits        10953    11998    +1045     
+ Misses       1053        9    -1044     

Impacted Files	Coverage Δ
evalml/utils/gen_utils.py	99.02% <ø> (+5.82%)	⬆️
evalml/tests/pipeline_tests/test_pipelines.py	100.00% <100.00%> (+4.13%)	⬆️
evalml/automl/automl_search.py	99.58% <0.00%> (+0.41%)	⬆️
evalml/tests/component_tests/test_components.py	100.00% <0.00%> (+0.51%)	⬆️
...s/prediction_explanations_tests/test_algorithms.py	100.00% <0.00%> (+1.11%)	⬆️
evalml/tests/component_tests/test_utils.py	100.00% <0.00%> (+3.57%)	⬆️
...derstanding/prediction_explanations/_algorithms.py	97.14% <0.00%> (+4.28%)	⬆️
evalml/tests/utils_tests/test_dependencies.py	100.00% <0.00%> (+6.25%)	⬆️
... and 18 more

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[freddyaboulton]

@bchen1116 I think it's ok to include LightGBM in automl! It outperformed XGBoost in a couple datasets while taking about the same time to fit!