How about excluding it using the exclude directive in the main springboot pom.xml file?

<dependencies>
  ...
  <dependency>
    <groupId>your.custom.library.groupId</groupId>
    <artifactId>artifactId</artifactId>
    ...
    <exclusions>
      <exclusion>
        <groupId>unwanted.test.dependency.groupId</groupId>
        <artifactId>artifactId</artifactId>
      </exclusion>
    </exclusions>
  </dependency>
</dependencies>