test: Fix race in testCreateContainerInPodUser()

That dialog switches between the "All" and "Local" filter of images.
The busybox image is shown in both views; however, it gets re-rendered
on switch, so clicking on it is a race condition -- without waiting the
click often goes to the *old* "All" result.

We can't directly wait on that transition. So switch to the "docker.io"
filter first, wait for the "No images found", and then switch to
"Local", so that our `wait_visible()` can take over.

test/check-application

@@ -2731,6 +2731,10 @@ class TestApplication(testlib.MachineCase):
 
         b.set_input_text("#run-image-dialog-name", container_name)
         b.set_input_text("#create-image-image-select-typeahead", IMG_BUSYBOX_LATEST)
+        # we want to switch to "Local", but to make waiting for IMG_BUSYBOX race-free, we first need to
+        # switch to another view
+        b.click('button.pf-v5-c-toggle-group__button:contains("docker.io")')
+        b.wait_in_text(".pf-v5-c-select__menu-list", "No images found")
         b.click('button.pf-v5-c-toggle-group__button:contains("Local")')
         b.click(f'button.pf-v5-c-select__menu-item:contains("{IMG_BUSYBOX_LATEST}")')
         b.click('.pf-v5-c-modal-box__footer #create-image-create-run-btn')