Bump org.codehaus.mojo:buildnumber-maven-plugin from 3.2.0 to 3.2.1

Bumps [org.codehaus.mojo:buildnumber-maven-plugin](https://github.com/mojohaus/buildnumber-maven-plugin) from 3.2.0 to 3.2.1.
- [Release notes](https://github.com/mojohaus/buildnumber-maven-plugin/releases)
- [Commits](mojohaus/buildnumber-maven-plugin@3.2.0...3.2.1)

---
updated-dependencies:
- dependency-name: org.codehaus.mojo:buildnumber-maven-plugin
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

pom.xml

@@ -71,7 +71,7 @@
     <io7m.bnd-resolver-maven-plugin.version>7.0.0</io7m.bnd-resolver-maven-plugin.version>
     <io7m.bnd.plugins.version>6.2.0</io7m.bnd.plugins.version>
     <io7m.build-helper-maven-plugin.version>3.6.0</io7m.build-helper-maven-plugin.version>
-    <io7m.buildnumber-maven-plugin.version>3.2.0</io7m.buildnumber-maven-plugin.version>
+    <io7m.buildnumber-maven-plugin.version>3.2.1</io7m.buildnumber-maven-plugin.version>
     <io7m.checksum-maven-plugin.version>1.11</io7m.checksum-maven-plugin.version>
     <io7m.cyclonedx-maven-plugin.version>2.8.1</io7m.cyclonedx-maven-plugin.version>
     <io7m.exec-maven-plugin.version>3.4.1</io7m.exec-maven-plugin.version>