Multi module liquibase project - spring-boot

Question

I have a multi module spring boot application backed by maven. There is a parent pom.xml which defines all the dependencies. There are 2 modules A and B. Module B is dependent on module A. Both the modules are spring applications and I have repackaged them as jars so that the interdependency between the modules would work. My application runs fine, but I have a problem while generating the liquibase diffs. My module A and B have got all the domain/hibernate entities. The Parent does not have any code. It just has the pom.xml.
When I do a mvn liquibase:diff from the parent, I get
Error setting up or running Liquibase: javax.persistence.PersistenceException: Unable to resolve persistence unit root URL: class path resource [] cannot be resolved to URL because it does not exist
When I do a mvn liquibase:diff from the module B, I get (I have the dependency defined in the parent pom)
Failed to execute goal org.liquibase:liquibase-maven-plugin:3.5.5:diff (default-cli) on project leave: Execution default-cli of goal org.liquibase:liquibase-maven-plugin:3.5.5:diff failed: Plugin org.liquibase:liquibase-maven-plugin:3.5.5 or one of its dependencies could not be resolved: Could not find artifact org.springframework.boot:spring-boot-starter-data-jpa:jar:1.0-SNAPSHOT -> [Help 1]
I dont know if restructuring the jars in the parent pom with the following code which got the application working is causing this problem.
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<id>repackage</id>
<configuration>
<classifier>exec</classifier>
</configuration>
</execution>
</executions>
</plugin>
Parent POM.xml and it has got a bit list of all the dependencies and plugins
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.xxx</groupId>
<artifactId>parent</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>pom</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.4.RELEASE</version>
</parent>
<modules>
<module>A</module>
<module>B</module>
</modules>
A Pom.xml
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.xxx</groupId>
<artifactId>parent</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<artifactId>A</artifactId>
<packaging>jar</packaging>
<properties>
<java.version>1.8</java.version>
</properties>
</project>
b Pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.xxx</groupId>
<artifactId>parent</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<artifactId>B</artifactId>
<packaging>jar</packaging>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.xxx</groupId>
<artifactId>A</artifactId>
<version>1.0-SNAPSHOT</version>
<scope>compile</scope>
</dependency>
</dependencies>
</project>