Merge pull request package-url#60 from package-url/dependabot/maven/org.apache.maven.plugins-maven-compiler-plugin-3.9.0

Bump maven-compiler-plugin from 3.8.1 to 3.9.0

Author: stevespringett

pom.xml

@@ -44,7 +44,7 @@
         <maven.javadoc.failOnError>false</maven.javadoc.failOnError>
         <project.build.outputTimestamp>1</project.build.outputTimestamp>
         <!-- Maven Plugin Versions -->
-        <maven.compiler.plugin.version>3.8.1</maven.compiler.plugin.version>
+        <maven.compiler.plugin.version>3.9.0</maven.compiler.plugin.version>
         <maven.jar.plugin.version>3.2.0</maven.jar.plugin.version>
         <maven.javadoc.plugin.version>3.3.1</maven.javadoc.plugin.version>
         <maven.release.plugin.version>3.0.0-M4</maven.release.plugin.version>