[FIX] hr_holidays: display option layout

=== ISSUE ===

If you navigate to Time Off > Configuration > Time Off Types and open a
type, the layout of the display option is not consistent.

The option should be displayed under the title and not next to it.

=== AFTER ===

We remove the empty `group` tag and add the `string` attribute to the
second one, in order to fix he layout.

task-3332666
part of task-3326263

closes odoo/odoo#124403

X-original-commit: cdd41cef07cb82b37e7c09b8f4a622ac7dde81a3
Signed-off-by: Kevin Baptiste <kba@odoo.com>

addons/hr_holidays/static/src/radio_image_field/radio_image_field.xml

@@ -2,7 +2,7 @@
 <templates id="template" xml:space="preserve">
 
     <t t-name="hr_holidays.RadioImageField" owl="1">
-        <div role="radiogroup" class="d-flex flex-wrap" t-att-aria-label="string">
+        <div role="radiogroup" class="d-flex flex-wrap gap-4" t-att-aria-label="string">
             <t t-if="props.readonly">
                 <t t-if="value !== false">
                     <div>

addons/hr_holidays/views/hr_leave_type_views.xml

@@ -79,13 +79,9 @@
                             <field name="allocation_validation_type" string="Approval" widget="radio" attrs="{'invisible': ['|', ('requires_allocation', '=', 'no'), ('employee_requests', '=', 'no')]}"/>
                         </group>
                     </group>
-                    <group name="visual" id="visual" >
-                        <group colspan="2" string="Display Option">
-                        </group>
-                        <group colspan="2">
-                            <field name="color" widget="color_picker" />
-                            <field class="o_time_off_icon_types d-flex flex-wrap" name="icon_id" widget="hr_holidays_radio_image" options="{'horizontal': true}"/>
-                        </group>
+                    <group name="visual" id="visual" string="Display Option" class="mw-100 col-lg-12">
+                        <field name="color" widget="color_picker" />
+                        <field class="o_time_off_icon_types d-flex flex-wrap" name="icon_id" widget="hr_holidays_radio_image" options="{'horizontal': true}"/>
                     </group>
                 </sheet>
             </form>