nb-select with empty value

[SashaSkywalker]

Issue type

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• bug report
• feature request

Current behavior:
nb-select render empty string in label for option with empty value

Expected behavior:
nb-select should render option label

Steps to reproduce:

<nb-select>
  <nb-option value=''>first</nb-option>
  <nb-option value='2'>second</nb-option>
</nb-select>

if user selects first option then nothing will be rendered in label (bad)
if user selects second option then second will be rendered in label (good)

[theroozbeh]

The same thing happens when value equals to number 0 in case of assigning numbers to values.
for example:

<nb-select>
  <nb-option [value]="0">
     first
   </nb-option>
   <nb-option [value]="1">
     second
  </nb-option>
</nb-select>

or: https://stackblitz.com/edit/nb-select-zero-issue

[aefox]

PR for fix opened in #1282

[yggg]

Closing as fix (#1282) was merged