feat(autocomplete): input for focus on value change

[jornetsimon]

An input to control the focus behaviour when the control value changes

Please read and mark the following check list before creating a pull request:

• I read and followed the CONTRIBUTING.md guide.
• I read and followed the New Feature Checklist guide.

Short description of what this resolves:

Ref #2355
Introduces an Input to NbAutocompleteDirective to control the focus behaviour when the control value is set (-> writeValue).

[codecov]

Codecov Report

Merging #2356 into master will increase coverage by 0.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #2356      +/-   ##
==========================================
+ Coverage   81.53%   81.54%   +0.01%     
==========================================
  Files         244      244              
  Lines        7377     7382       +5     
  Branches      773      774       +1     
==========================================
+ Hits         6015     6020       +5     
+ Misses       1135     1132       -3     
- Partials      227      230       +3     

Impacted Files	Coverage Δ
.../components/autocomplete/autocomplete.directive.ts	81.29% <66.66%> (-0.71%)	⬇️
...endar-kit/services/calendar-month-model.service.ts	96.07% <0.00%> (-1.97%)	⬇️
...ramework/theme/components/toastr/toastr.service.ts	97.39% <0.00%> (+2.60%)	⬆️

[yggg]

Thanks 👍