Bump org.apache.maven.plugins:maven-source-plugin from 3.3.1 to 3.4.0 (#471)

Author: jonesbusy

pom.xml

@@ -84,7 +84,7 @@
     <maven-enforcer-plugin.version>3.6.2</maven-enforcer-plugin.version>
     <maven-jar-plugin.version>3.5.0</maven-jar-plugin.version>
     <maven-javadoc-plugin.version>3.12.0</maven-javadoc-plugin.version>
-    <maven-source-plugin.version>3.3.1</maven-source-plugin.version>
+    <maven-source-plugin.version>3.4.0</maven-source-plugin.version>
     <maven-release-plugin.version>3.2.0</maven-release-plugin.version>
     <maven-gpg-plugin.version>3.2.8</maven-gpg-plugin.version>
     <central-publishing-maven-plugin.version>0.9.0</central-publishing-maven-plugin.version>