fix(scope-manager): correct analysis of abstract class properties

[bradzacher]

Fixes #2417

[typescript-eslint]

Thanks for the PR, @bradzacher!

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[codecov]

Codecov Report

Merging #2420 into v4 will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##               v4    #2420   +/-   ##
=======================================
  Coverage   92.94%   92.94%           
=======================================
  Files         288      288           
  Lines        9246     9247    +1     
  Branches     2572     2572           
=======================================
+ Hits         8594     8595    +1     
  Misses        320      320           
  Partials      332      332           

Flag	Coverage Δ
#unittest	92.94% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...ackages/scope-manager/src/referencer/Referencer.ts	93.85% <100.00%> (+0.02%)	⬆️