Await cert chain to catch up before asserting resumption in tests

Add extra wait to assert that a paused node is caught up with the cert
chain before waiting for an instance to be reached.

use additional wait timeout for chain catchup to make sure we avoid
flakage on CI.

Fixes: #1025

Author: masih

f3_test.go

@@ -120,6 +120,13 @@ func TestF3PauseResumeCatchup(t *testing.T) {
 	// Resuming node 1 should continue agreeing on instances.
 	env.resumeNode(1)
 	env.requireF3RunningEventually(eventualCheckTimeout, nodeMatchers.byID(1))
+	require.Eventually(t, func() bool {
+		node0LatestCert, err := env.nodes[0].f3.GetLatestCert(env.testCtx)
+		require.NoError(t, err)
+		node1LatestCert, err := env.nodes[1].f3.GetLatestCert(env.testCtx)
+		require.NoError(t, err)
+		return node0LatestCert.GPBFTInstance == node1LatestCert.GPBFTInstance
+	}, eventualCheckTimeout*3, eventualCheckInterval, "Node 1 did not catch up on certs")
 
 	// Wait until we're far enough that pure GPBFT catchup should be impossible.
 	targetInstance := env.nodes[1].currentGpbftInstance() + env.manifest.CommitteeLookback + 1