Error while creating mock network in CordaApp

Question

I'm writing unit test cases on workflows of my corda app while I'm initialising mock network and run it using command ./gradlew test I'm facing an error which is related to liquibase. Below is my code and error I'm facing

Code

@Before
    public void setup() {
        network = new MockNetwork(new MockNetworkParameters().withCordappsForAllNodes(ImmutableList.of(
                TestCordapp.findCordapp("net.corda.tokenizeddemocracy.contracts"),
                TestCordapp.findCordapp("net.corda.tokenizeddemocracy.flows.KafkaFlows")))
                .withNotarySpecs(ImmutableList.of(new MockNetworkNotarySpec(CordaX500Name.parse("O=Notary,L=London,C=GB"))))
        );
        a = network.createPartyNode(null);
        b = network.createPartyNode(null);
        network.runNetwork();
    }

Console

liquibase/exception/LiquibaseException
java.lang.NoClassDefFoundError: liquibase/exception/LiquibaseException
    at net.corda.node.internal.AbstractNode$startHikariPool$1.invoke(AbstractNode.kt:1024)
    at net.corda.node.internal.AbstractNode$startHikariPool$1.invoke(AbstractNode.kt:202)
    at net.corda.node.internal.AbstractNodeKt.startHikariPool(AbstractNode.kt:1343)
    at net.corda.node.internal.AbstractNode.startHikariPool(AbstractNode.kt:1023)
    at net.corda.node.internal.AbstractNode.startDatabase(AbstractNode.kt:1017)
    at net.corda.testing.node.internal.InternalMockNetwork$MockNode.startDatabase(InternalMockNetwork.kt:433)
    at net.corda.node.internal.AbstractNode.start(AbstractNode.kt:572)
    at net.corda.testing.node.internal.InternalMockNetwork$MockNode.start(InternalMockNetwork.kt:382)
    at net.corda.testing.node.internal.InternalMockNetwork.createNodeImpl(InternalMockNetwork.kt:501)