fix(select): resubscribe on options changes

[Tibing]

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

Short description of what this resolves:

Closes #931
Closes #948

[codecov]

Codecov Report

Merging #1009 into master will decrease coverage by <.01%.
The diff coverage is 81.25%.

@@            Coverage Diff             @@
##           master    #1009      +/-   ##
==========================================
- Coverage   76.89%   76.88%   -0.01%     
==========================================
  Files         200      200              
  Lines        5963     5975      +12     
  Branches      454      455       +1     
==========================================
+ Hits         4585     4594       +9     
- Misses       1271     1273       +2     
- Partials      107      108       +1

Impacted Files	Coverage Δ
...mework/theme/components/select/option.component.ts	92.3% <66.66%> (-4.76%)	⬇️
...mework/theme/components/select/select.component.ts	84.23% <90%> (+0.05%)	⬆️

[nnixaa]

LGTM

[Dhanushka-Sasanka]

<nb-select id="paymentMethod" formControlName="paymentMethod" fullWidth size="small"
                               (selectedChange)="getSelectedPaymentMethod($event)">
                      <nb-option *ngFor="let paymentType of paymentTypes"
                                 [value]="paymentType.id"  >{{paymentType.paymentTypeName}}
                      </nb-option>
</nb-select>

This way is working fine for me ...!