Update dependency org.apache.maven.plugins:maven-source-plugin to v3.4.0 (#617)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

pom.xml

@@ -51,7 +51,7 @@
     <maven-central-publishing-plugin.version>0.9.0</maven-central-publishing-plugin.version>
     <maven-gpg-plugin.version>3.2.8</maven-gpg-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-surefire-plugin.version>3.5.4</maven-surefire-plugin.version>
     <maven-shade-plugin.version>3.6.1</maven-shade-plugin.version>
     <maven-enforcer-plugin.version>3.6.2</maven-enforcer-plugin.version>