Add missing Maven plugin version properties

Co-authored-by: thomasturrell <1552612+thomasturrell@users.noreply.github.com>

Author: Copilot

pom.xml

@@ -18,6 +18,8 @@
     <java.version>25</java.version>
     <jacoco-maven-plugin.version>0.8.14</jacoco-maven-plugin.version>
     <maven-checkstyle-plugin.version>3.6.0</maven-checkstyle-plugin.version>
+    <maven-gpg-plugin.version>3.2.8</maven-gpg-plugin.version>
+    <central-publishing-maven-plugin.version>0.9.0</central-publishing-maven-plugin.version>
     <checkstyle.version>12.2.0</checkstyle.version>
     <lifecycle-mapping.version>1.0.0</lifecycle-mapping.version>
     <jjwt.version>0.13.0</jjwt.version>