fix(eslint-plugin): [typedef] handle AssignmentPattern inside TSParameterProperty

[mrmlnc]

What is the purpose of this pull request?

This is a potential fix for #921.

What changes did you make? (Give an overview)

The node with the TSParameterProperty type can contains the node with the AssignmentPattern type. In this case, we should check type annotations for the node with AssignmentPattern type.

class Something {
    // Works fine without `= {}`
    constructor(private readonly _options: Options = {}) {
        //         ^                 ^ AssignmentPattern
        //         | TSParameterProperty
        //                                               
    }
}

[typescript-eslint]

Thanks for the PR, @mrmlnc!

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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[codecov]

Codecov Report

Merging #923 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #923      +/-   ##
==========================================
+ Coverage   94.08%   94.08%   +<.01%     
==========================================
  Files         113      113              
  Lines        4916     4919       +3     
  Branches     1369     1371       +2     
==========================================
+ Hits         4625     4628       +3     
  Misses        165      165              
  Partials      126      126

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/typedef.ts	95.91% <100%> (+0.26%)	⬆️

[bradzacher]

LGTM, thanks for doing this!