[IMP] portal: increase search input width

Since the new filter in sale_timesheet, the search box size was no wide
any more to handle the placeholder text.

task-2409761

addons/portal/views/portal_templates.xml

@@ -296,7 +296,7 @@
                     </div>
                     <t t-raw="0"/>
                 </div>
-                <form t-if="searchbar_inputs" class="form-inline o_portal_search_panel ml-lg-4">
+                <form t-if="searchbar_inputs" class="form-inline o_portal_search_panel ml-lg-4 col-xl-4 col-md-5">
                     <div class="input-group input-group-sm w-100">
                         <div class="input-group-prepend">
                             <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown"/>