test: Add hack to avoid losing focus on #containers-filter

For some reason, .focus() sometimes does not take effect, and the
element immediately loses the focus again. This causes set_input_text()
to select the whole page text instead of the input element, and failing
to set the intended value.

test/check-application

@@ -373,6 +373,12 @@ class TestApplication(testlib.MachineCase):
         b.click(".pf-v5-c-modal-box button:contains('Force delete')")
         self.waitPodRow("pod-1", False)
 
+        # HACK: there is some race here which steals the focus from the filter input and selects the page text instead
+        for _ in range(3):
+            b.focus('#containers-filter')
+            time.sleep(1)
+            if b.eval_js('document.activeElement == document.querySelector("#containers-filter")'):
+                break
         b.set_input_text('#containers-filter', '')
         self.machine.execute("podman pod create --infra=false --name pod-2")
         self.waitPodContainer("pod-2", [])