gui_e2e: fix email notifications test

Replace missing 'Assignee filters' locator with 'Exclude services'
locator. This locator is only used to scroll down the page, in
this case it doesn't realy matter which one of the locators to use.

Change-Id: I2b597a0b4b726d3977363f4225c67d3f94d274da

tests/testlib/playwright/pom/setup/notification_rules.py

@@ -77,8 +77,8 @@ def _service_filters_button(self) -> Locator:
         return self.main_area.locator().get_by_role("button", name="Service filters")
 
     @property
-    def _assignee_filters_button(self):
-        return self.main_area.locator().get_by_role("button", name="Assignee filters")
+    def _exclude_services_checkbox(self):
+        return self.main_area.locator().get_by_role("checkbox", name="Exclude services")
 
     @property
     def services_checkbox(self) -> Locator:
@@ -161,7 +161,7 @@ def expand_service_filters(self) -> None:
         if self.services_checkbox.is_hidden():
             self._service_filters_button.click()
         # The scrollbar interrupts the interaction with services checkbox -> scroll into view
-        self._assignee_filters_button.scroll_into_view_if_needed()
+        self._exclude_services_checkbox.scroll_into_view_if_needed()
 
     def apply_services_filter(self, service_name: str) -> None:
         self.expand_service_filters()