fix(typescript-estree): correct type of ArrayPattern.elements

[bradzacher]

#1450 pointed out that the type is incorrect. The parser assigns null if the element in the pattern is empty, but the types were non-nullable.

[typescript-eslint]

Thanks for the PR, @bradzacher!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[armano2]

/home/vsts/work/1/s/packages/eslint-plugin/src/rules/indent-new-do-not-use/index.ts
  859:51  error  Prefer using nullish coalescing operator (`??`) instead of a logical or (`||`), as it is a safer operator  @typescript-eslint/prefer-nullish-coalescing

[codecov]

Codecov Report

Merging #1451 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #1451      +/-   ##
=========================================
+ Coverage    94.1%   94.1%   +<.01%     
=========================================
  Files         143     143              
  Lines        6458    6459       +1     
  Branches     1824    1824              
=========================================
+ Hits         6077    6078       +1     
  Misses        204     204              
  Partials      177     177

Impacted Files	Coverage Δ
...nt-plugin/src/rules/indent-new-do-not-use/index.ts	98.4% <100%> (ø)	⬆️