Implement removing and adding qualifications while creating or editing employees (#29)

Co-authored-by: Phan Huy Tran <p.tran@neusta.de>
Reviewed-on: #29
Reviewed-by: Constantin Simonis <constantin@simonis.lol>

src/app/employee/create/create.component.html

@@ -36,6 +36,15 @@
         <input matInput formControlName="phone" required>
       </mat-form-field>
 
+      <mat-form-field class="!w-full">
+        <mat-label>Qualifications</mat-label>
+        <mat-select formControlName="qualifications" multiple>
+          <mat-option *ngFor="let qualification of qualifications" [value]="qualification.id">
+            {{qualification.skill}}
+          </mat-option>
+        </mat-select>
+      </mat-form-field>
+
       <mat-dialog-actions align="end">
         <button mat-button mat-dialog-close>Cancel</button>
         <button mat-flat-button color="primary" type="submit">Submit</button>