Fix "caddy-frontend/test: Cover ATS cases for timeouts"

As timeout is the same on frontend caddy, ATS and backend caddy allow
0 or 1 accesses to the additional endpoints. The request might not reach
the backend caddy, and this is expected.

software/caddy-frontend/test/test.py

@@ -3502,10 +3502,8 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
         if pattern.match(line):
           matching_line_amount += 1
 
-    # Caddy used between ATS and the backend received only one connection
-    self.assertEqual(
-      1,
-      matching_line_amount)
+    # Caddy used between ATS and the backend received maximum one connection
+    self.assertIn(matching_line_amount, [0, 1])
 
     timeout = 5
     b = time.time()
@@ -3540,10 +3538,8 @@ http://apachecustomhttpsaccepted.example.com:%%(http_port)s {
         break
       time.sleep(0.1)
 
-    # ATS has only one entry for this query
-    self.assertEqual(
-      1,
-      matching_line_amount)
+    # ATS has maximum one entry for this query
+    self.assertIn(matching_line_amount, [0, 1])
 
     # the result is available immediately after
     result = fakeHTTPResult(