[IMP] crm: underline datepicker field in PLS settings

Make the date field always underlined in the PLS modal in
the settings, to indicate that it is editable and not a
technical constraint.

Also rename confirm button to "update".

Task-3193113

closes odoo/odoo#114223

Signed-off-by: Warnon Aurélien (awa) <awa@odoo.com>

addons/crm/wizard/crm_lead_pls_update_views.xml

@@ -12,11 +12,11 @@
                     <field name="pls_fields" widget="many2many_tags" placeholder="Extra fields..."/>
                 </p>
                 <p>
-                    Consider leads created as of the: <field name="pls_start_date"/>
+                    Consider leads created as of the: <field name="pls_start_date" class="o_field_highlight"/>
                 </p>
                 <footer>
                     <button name="action_update_crm_lead_probabilities" type="object"
-                        string="Confirm" class="btn-primary" data-hotkey="q"/>
+                        string="Update" class="btn-primary" data-hotkey="q"/>
                     <button special="cancel" data-hotkey="z" string="Cancel"/>
                 </footer>
             </form>