[FIX] web: adapt BS import and assets to BS update

addons/web/static/src/scss/import_bootstrap.scss

@@ -35,9 +35,11 @@
 @import "media";
 @import "list-group";
 @import "close";
+@import "toasts";
 @import "modal";
 @import "tooltip";
 @import "popover";
 @import "carousel";
+@import "spinners";
 @import "utilities";
 @import "print";

addons/web/views/webclient_templates.xml

@@ -94,6 +94,7 @@
         <script type="text/javascript" src="/web/static/lib/bootstrap/js/popover.js"></script>
         <script type="text/javascript" src="/web/static/lib/bootstrap/js/scrollspy.js"></script>
         <script type="text/javascript" src="/web/static/lib/bootstrap/js/tab.js"></script>
+        <script type="text/javascript" src="/web/static/lib/bootstrap/js/toast.js"></script>
 
         <script type="text/javascript" src="/web/static/lib/tempusdominus/tempusdominus.js"/>
         <script type="text/javascript" src="/web/static/lib/select2/select2.js"></script>