java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory

Add a SLF4J implementation (as you only have its API):

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.7.26</version>
</dependency>

You have to provide one of the various SLF4J implementation .jar files in the classpath, as well as the interface .jar file. This is documented.