[FIX] point_of_sale: broken view of the NumberPopup

To reproduce:

1. Activate pos_hr feature.
2. Authorize an employee with pin.
3. Open a pos session and login with that employee.
4. [BUG] The popup to input pin is broken.

This is because of the 'minus' button. In this commit, we make sure
to hide the 'minus' button when the popup is used to ask for pin.

closes odoo/odoo#66688

Signed-off-by: pimodoo <pimodoo@users.noreply.github.com>

addons/point_of_sale/static/src/xml/Popups/NumberPopup.xml

@@ -35,7 +35,7 @@
                         <button class="input-button number-char" t-on-mousedown.prevent="sendInput('7')">7</button>
                         <button class="input-button number-char" t-on-mousedown.prevent="sendInput('8')">8</button>
                         <button class="input-button number-char" t-on-mousedown.prevent="sendInput('9')">9</button>
-                        <button class="input-button number-char" t-on-mousedown.prevent="sendInput('-')">-</button>
+                        <button t-if="!props.isPassword" class="input-button number-char" t-on-mousedown.prevent="sendInput('-')">-</button>
                         <br />
                         <button class="input-button numpad-char" t-on-mousedown.prevent="sendInput('Delete')">C</button>
                         <button class="input-button number-char" t-on-mousedown.prevent="sendInput('0')">0</button>