test(alerts): the widget test reads the time as |ago writes it (#5510)

Under an hour |ago says "12m 3s ago", so the test looks for the minutes
alone; the reading cell drops an empty class.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/core/test_alerts_widget.py

@@ -65,9 +65,9 @@ async def test_firing_and_silent_come_first_then_who_acknowledged(app):
     assert re.search(r'w-verdict tone-crit">\s*1 firing, 1 silent, 1 acknowledged\.', page)
     assert page.index("web-1 CPU high") < page.index("nas agent") < page.index("db disk")
     assert 'href="/alerts/history?rule=r1"' in page
-    assert "web-1 · fires on CPU &gt; 90%" in page and "94%" in page and "12m ago" in page
+    assert "web-1 · fires on CPU &gt; 90%" in page and ">94%<" in page and ">12m " in page
     assert "nas · no reading" in page
-    assert "db-1:/var · acknowledged by bryan" in page and "40m ago" in page
+    assert "db-1:/var · acknowledged by bryan <time" in page and ">40m " in page
     assert "+1 rule quiet" in page and 'href="/alerts/"' in page
     assert len(re.findall(r"<th[ >]", page)) == 3
     assert not hex_colours(page), hex_colours(page)