test-network: add test case for issue #32186

The reporter said that the issue is caused by BindCarrier=, but
I cannot reproduce it. Anyway, let's test it.

test/test-network/conf/25-bond99.network

@@ -5,3 +5,4 @@ Name=bond99
 [Network]
 IPv6AcceptRA=no
 Address=192.168.123.45/24
+BindCarrier=dummy98 test1

test/test-network/systemd-networkd-tests.py

@@ -5862,6 +5862,10 @@ class NetworkdBondTests(unittest.TestCase, Utilities):
         print(output)
         self.assertRegex(output, 'MASTER,UP,LOWER_UP')
 
+        # test case for issue #32186
+        restart_networkd()
+        self.wait_online('dummy98:enslaved', 'test1:enslaved', 'bond99:routable')
+
         self.wait_operstate('dummy98', 'enslaved')
         self.wait_operstate('test1', 'enslaved')
         self.wait_operstate('bond99', 'routable')