(test/fix) race condition in network bridge advisory subscription initialization in AMQ6366Test

[gurpartap3697]

Description

This PR fixes a race condition in the network bridge setup that cause missed advisory messages and prevent durable demand subscriptions from being created.

waitForBridgeFormation() returned as soon as remoteBrokerName was set during collectBrokerInfos() and this occurs before startRemoteBridge() registers the advisory consumer on conBroker.

In some cases following sequence occur:

1. waitForBridgeFormation() returns early
2. sub1 is created
3. Its advisory message is fired
4. The bridge advisory consumer is not yet registered on `conBroker
5. The advisory is missed
6. Durable demand subscription is never created on pubBroker

The fix ensures proper synchronization by waiting until the bridge’s advisory consumer is fully registered before proceeding. Now, it wait for at least one topic-region subscription on 1conBroker1

Error

AMQ6366Test>CombinationTestSupport.runBare:113->CombinationTestSupport.runBare:107->testDuplexDurableSubRestarted:54->testNonDurableReceiveThrougRestart:109 Network durable subscription should be active on BrokerA

ref - https://github.com/apache/activemq/actions/runs/23763076486/job/69370689090

Test

Ran test locally over 50 times with 100% success rate. Previously, test was failing consistently 5 out of 50 times (10% failure rate).

[cshannon]

@gurpartap3697 - Thanks for the fix! I noticed this the other day on a couple of my PRs but didn't get a chance to look at it yet.

[cshannon]

I'll let the GH actions run before merging just in case