feat(typeahead): add more cases for on blur logic

[daniloff200]

closes #5360

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• built and tested the changes locally.
• added/updated tests.
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[codecov]

Codecov Report

Merging #5629 into development will decrease coverage by 0.00%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #5629      +/-   ##
===============================================
- Coverage        73.66%   73.65%   -0.01%     
===============================================
  Files              323      323              
  Lines            11614    11618       +4     
  Branches          2473     2475       +2     
===============================================
+ Hits              8555     8557       +2     
- Misses            1962     1965       +3     
+ Partials          1097     1096       -1     

Impacted Files	Coverage Δ
...ker/themes/bs/bs-months-calendar-view.component.ts	56.25% <0.00%> (-12.50%)	⬇️
src/datepicker/reducer/bs-datepicker.effects.ts	74.07% <0.00%> (-1.49%)	⬇️
src/typeahead/typeahead.directive.ts	79.92% <0.00%> (-1.21%)	⬇️
.../datepicker/bs-daterangepicker-inline.component.ts	62.35% <0.00%> (+1.17%)	⬆️
src/datepicker/utils/bs-calendar-utils.ts	84.84% <0.00%> (+6.06%)	⬆️
...themes/bs/bs-datepicker-day-decorator.directive.ts	81.48% <0.00%> (+7.40%)	⬆️
src/datepicker/engine/flag-days-calendar.ts	82.85% <0.00%> (+8.57%)	⬆️

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