feat: add max-element-depth rule

[yeonjuan]

fixes #65

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.42%. Comparing base (5840332) to head (6a427ac).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #261      +/-   ##
==========================================
+ Coverage   98.40%   98.42%   +0.01%     
==========================================
  Files          65       66       +1     
  Lines        1822     1843      +21     
  Branches      499      505       +6     
==========================================
+ Hits         1793     1814      +21     
  Misses         29       29              

Flag	Coverage Δ
unittest	98.42% <100.00%> (+0.01%)	⬆️

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Files with missing lines	Coverage Δ
packages/eslint-plugin/lib/rules/index.js	100.00% <100.00%> (ø)
...kages/eslint-plugin/lib/rules/max-element-depth.js	100.00% <100.00%> (ø)