Adjust test to avoid spurious failures
Adjust test to avoid spurious failures

Previously, if the two random numbers happened to be equal, the block time
would not be updated, and subsequent checks would fail.

bitcoinsSG/zcash,CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,bitcoinsSG/zcash,CTRoundTable/Encrypted.Cash,bitcoinsSG/zcash,CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,bitcoinsSG/zcash,bitcoinsSG/zcash,bitcoinsSG/zcash