[IMP] web: Add zoom on employee avatar

This commit enables the zoom on mobile.

To avoid any issue in website, we first only activate it in the backend.
Note that it's not, strictly speaking, a zoom. It only shows the
original size of the picture.

Steps to reproduce:
* Open Employee
* Select an employee
* Touch on the photos

closes odoo/odoo#75785

Signed-off-by: Adrien Dieudonné (adr) <adr@odoo.com>

addons/web/static/src/legacy/js/fields/basic_fields.js

@@ -2198,6 +2198,7 @@ var FieldBinaryImage = AbstractFieldBinary.extend({
                     timer: zoomDelay,
                     attach: '.o_content',
                     attachToTarget: true,
+                    disabledOnMobile: false,
                     onShow: function () {
                         var zoomHeight = Math.ceil(this.$zoom.height());
                         var zoomWidth = Math.ceil(this.$zoom.width());