[FIX] web: TempusDominus unsafe access to config

During TempusDominus autobinding to fields matching its default classes
(like `.datetimepicker-input` used by our DatePicker widget) and no
config was previously provided to the library (like when we disable it
on mobile), an unsafe access to the config's `_options` property results
into an error as the config is `undefined`.

This commit fixes it by first checking for config existence before
attempting to access its property.

Note: as this is a fix inside a library, a comment is added to make
clear. Also similar fixes where already done in the same file.

opw-2242880

X-original-commit: fe1f7c3e361bbd249b4025a464c546f478b6e989

addons/web/static/lib/tempusdominus/tempusdominus.js

@@ -2777,7 +2777,8 @@ var TempusDominusBootstrap4 = function ($) {
         if ($target.length === 0) {
             return;
         }
-        if (!config._options.allowInputToggle) {
+        // /!\ ODOO FIX: check on 'config' existence added by odoo
+        if (!(config && config._options.allowInputToggle)) {
             return;
         }
         TempusDominusBootstrap4._jQueryInterface.call($target, 'show', event);