Upgraded sortpom-maven-plugin from 2.8.0 to 2.9.0 (#57)

Bumps [sortpom-maven-plugin](https://github.com/Ekryd/sortpom) from 2.8.0 to 2.9.0.
- [Release notes](https://github.com/Ekryd/sortpom/releases)
- [Commits](Ekryd/sortpom@sortpom-parent-2.8.0...sortpom-parent-2.9.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

pom.xml

@@ -286,7 +286,7 @@
       <plugin>
         <groupId>com.github.ekryd.sortpom</groupId>
         <artifactId>sortpom-maven-plugin</artifactId>
-        <version>2.8.0</version>
+        <version>2.9.0</version>
         <configuration>
           <predefinedSortOrder>custom_1</predefinedSortOrder>
           <encoding>${project.build.sourceEncoding}</encoding>