Bump org.apache.maven.plugins:maven-gpg-plugin from 3.2.7 to 3.2.8

Bumps [org.apache.maven.plugins:maven-gpg-plugin](https://github.com/apache/maven-gpg-plugin) from 3.2.7 to 3.2.8.
- [Release notes](https://github.com/apache/maven-gpg-plugin/releases)
- [Commits](apache/maven-gpg-plugin@maven-gpg-plugin-3.2.7...maven-gpg-plugin-3.2.8)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-gpg-plugin
  dependency-version: 3.2.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

pom.xml

@@ -69,7 +69,7 @@
         <spotbugs-maven-plugin.version>4.9.3.2</spotbugs-maven-plugin.version>
         <spotbugs.version>4.9.3</spotbugs.version>
         <buildnumber.plugin.version>3.2.1</buildnumber.plugin.version>
-        <maven.gpg.plugin.version>3.2.7</maven.gpg.plugin.version>
+        <maven.gpg.plugin.version>3.2.8</maven.gpg.plugin.version>
         <asciidoctor.maven.plugin.version>3.2.0</asciidoctor.maven.plugin.version>
         <asciidoctorj.version>3.0.0</asciidoctorj.version>
         <asciidoctorj.diagram.version>3.0.1</asciidoctorj.diagram.version>