Bump maven-source-plugin from 3.1.0 to 3.2.1

Bumps [maven-source-plugin](https://github.com/apache/maven-source-plugin) from 3.1.0 to 3.2.1.
- [Release notes](https://github.com/apache/maven-source-plugin/releases)
- [Commits](apache/maven-source-plugin@maven-source-plugin-3.1.0...maven-source-plugin-3.2.1)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-source-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

preferencesfx-demo/pom.xml

@@ -21,7 +21,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-source-plugin</artifactId>
-                <version>3.1.0</version>
+                <version>3.2.1</version>
                 <executions>
                     <execution>
                         <id>attach-sources</id>

preferencesfx/pom.xml

@@ -75,7 +75,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-source-plugin</artifactId>
-                <version>3.1.0</version>
+                <version>3.2.1</version>
                 <executions>
                     <execution>
                         <id>attach-sources</id>