[FIX] web: prevent false test fail

The commit [1] removed two async module and caused a reorganisation
on the module loading.
Since that commit, two tests that throw an error failed
because the error message was written in the console
and the server considered this as a test fail.
Now, the error message is not written in the console anymore.

[1]: 96687f29496ab4cf16ae2ab1584ef1a6a3fb4a11

Part-of: odoo/odoo#121185

addons/web/static/tests/views/form/form_view_tests.js

@@ -13041,6 +13041,13 @@ QUnit.module("Views", (hooks) => {
     QUnit.test(
         "coming to an action with an error from a form view with a dirty x2m",
         async function (assert) {
+            const handler = (ev) => {
+                // need to preventDefault to remove error from console (so python test pass)
+                ev.preventDefault();
+            };
+            window.addEventListener("unhandledrejection", handler);
+            registerCleanup(() => window.removeEventListener("unhandledrejection", handler));
+
             class TestClientAction extends Component {
                 setup() {
                     throw new Error("Something went wrong");
@@ -13124,6 +13131,13 @@ QUnit.module("Views", (hooks) => {
     QUnit.test(
         "coming to an action with an error from a form view with a record in creation",
         async function (assert) {
+            const handler = (ev) => {
+                // need to preventDefault to remove error from console (so python test pass)
+                ev.preventDefault();
+            };
+            window.addEventListener("unhandledrejection", handler);
+            registerCleanup(() => window.removeEventListener("unhandledrejection", handler));
+
             class TestClientAction extends Component {
                 setup() {
                     throw new Error("Something went wrong");