Fix Model Family repr

[bchen1116]

fix #1112

Fix so that the representation of model family is understandable.

[codecov]

Codecov Report

Merging #1165 into main will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1165   +/-   ##
=======================================
  Coverage   99.91%   99.91%           
=======================================
  Files         197      197           
  Lines       11653    11663   +10     
=======================================
+ Hits        11643    11653   +10     
  Misses         10       10           

Impacted Files	Coverage Δ
evalml/model_family/model_family.py	100.00% <100.00%> (ø)
...alml/tests/model_family_tests/test_model_family.py	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8ca9acb...96b5742. Read the comment docs.

[jeremyliweishih]

Looks good! One more thing to add would be a test case to ensure the output of the list of enums would not appear as [, , , ,]. I think you can achieve this by calling repr([enums]). Might be good to add the same for printing the list as well.

[angela97lin]

I agree with Jeremy's comments but otherwise LGTM!

[jeremyliweishih]

LGTM