tests: Fix MaxConnectionsPerIP setting in agreement/gossip tests

* algorand#6171 decreased MaxConnectionsPerIP default value and it is not
  enough for agreement/gossip tests

agreement/gossip/networkFull_test.go

@@ -362,6 +362,7 @@ func testNetworkImplFull(t *testing.T, nodesCount int) {
 	// which is a different test of logic that agremeent needs to
 	// deal with.
 	cfg := config.GetDefaultLocal()
+	cfg.MaxConnectionsPerIP = nodesCount
 	cfg.AgreementIncomingVotesQueueLength = 100
 	cfg.AgreementIncomingProposalsQueueLength = 100
 	cfg.AgreementIncomingBundlesQueueLength = 100