Make secret rendering test more resilient to implementation details (#…

…28673)

The newly released Pygments 2.14.0 changed slightly the way it
wraps tags around rendeered variables and tour test made far
too many assumptions about the rendered output which started to
fail on main with the new Pygments.

This PR fixes it by actually testing only what it was supposed
to test:
- lack of the secret in rendered output
- presence of *** masking in the output

tests/www/views/test_views_rendered.py

@@ -30,7 +30,7 @@
 from airflow.utils.state import DagRunState, TaskInstanceState
 from airflow.utils.types import DagRunType
 from tests.test_utils.db import clear_db_dags, clear_db_runs, clear_rendered_ti_fields
-from tests.test_utils.www import check_content_in_response
+from tests.test_utils.www import check_content_in_response, check_content_not_in_response
 
 DEFAULT_DATE = timezone.datetime(2020, 3, 1)
 
@@ -186,7 +186,7 @@ def test_user_defined_filter_and_macros_raise_error(admin_client, create_dag_run
 @pytest.mark.usefixtures("patch_app")
 def test_rendered_template_secret(admin_client, create_dag_run, task_secret):
     """Test that the Rendered View masks values retrieved from secret variables."""
-    Variable.set("my_secret", "foo")
+    Variable.set("my_secret", "secret_unlikely_to_happen_accidentally")
     Variable.set("spam", "egg")
 
     assert task_secret.bash_command == "echo {{ var.value.my_secret }} && echo {{ var.value.spam }}"
@@ -202,8 +202,7 @@ def test_rendered_template_secret(admin_client, create_dag_run, task_secret):
     url = f"rendered-templates?task_id=task_secret&dag_id=testdag&execution_date={date}"
 
     resp = admin_client.get(url, follow_redirects=True)
-    check_content_in_response(
-        'echo</span> *** <span class="o">&amp;&amp;</span> <span class="nb">echo</span> egg', resp
-    )
+    check_content_in_response("***", resp)
+    check_content_not_in_response("secret_unlikely_to_happen_accidentally", resp)
     ti.refresh_from_task(task_secret)
     assert ti.state == TaskInstanceState.QUEUED