feat(typeahead): add scroll support

[IlyaSurmay]

Closes #1168

• read and followed the CONTRIBUTING.md guide.
• built and tested the changes locally.
• added/updated tests.
• added/updated API documentation.
• added/updated demos.

[codecov]

Codecov Report

Merging #2821 into development will increase coverage by 0.3%.
The diff coverage is 71.01%.

@@              Coverage Diff               @@
##           development    #2821     +/-   ##
==============================================
+ Coverage        70.44%   70.75%   +0.3%     
==============================================
  Files              137      137             
  Lines             4094     4151     +57     
  Branches           712      732     +20     
==============================================
+ Hits              2884     2937     +53     
+ Misses             912      910      -2     
- Partials           298      304      +6

Impacted Files	Coverage Δ
src/typeahead/typeahead.directive.ts	71.8% <42.85%> (-0.09%)	⬇️
src/typeahead/typeahead-container.component.ts	79.83% <78.18%> (+6.98%)	⬆️
src/utils/utils.class.ts	80% <0%> (+30%)	⬆️

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