Fix Raft UT flake by prolong eventual timeout

FAB-16903 #done

Change-Id: Ie39bcdbbc4f3951ac814d6f00d7a275e901bc8b6
Signed-off-by: Jay Guo <guojiannan1101@gmail.com>

orderer/consensus/etcdraft/chain_test.go

@@ -592,7 +592,7 @@ var _ = Describe("Chain", func() {
 								Consistently(support.WriteConfigBlockCallCount).Should(Equal(0))
 
 								clock.Increment(30 * time.Minute)
-								Eventually(support.WriteBlockCallCount).Should(Equal(1))
+								Eventually(support.WriteBlockCallCount, LongEventualTimeout).Should(Equal(1))
 							})
 						})
 					})