Bump the standard-plugins group across 1 directory with 2 updates

Bumps the standard-plugins group with 2 updates in the / directory: [org.codehaus.mojo:flatten-maven-plugin](https://github.com/mojohaus/flatten-maven-plugin) and [org.apache.maven.plugins:maven-gpg-plugin](https://github.com/apache/maven-gpg-plugin).


Updates `org.codehaus.mojo:flatten-maven-plugin` from 1.7.1 to 1.7.2
- [Release notes](https://github.com/mojohaus/flatten-maven-plugin/releases)
- [Commits](mojohaus/flatten-maven-plugin@1.7.1...1.7.2)

Updates `org.apache.maven.plugins: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.codehaus.mojo:flatten-maven-plugin
  dependency-version: 1.7.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: standard-plugins
- dependency-name: org.apache.maven.plugins:maven-gpg-plugin
  dependency-version: 3.2.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: standard-plugins
...

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

Author: dependabot[bot]

pom.xml

@@ -59,14 +59,14 @@
         <maven.compiler.target>17</maven.compiler.target>
 
         <!-- plugin versions -->
-        <flatten-maven-plugin.version>1.7.1</flatten-maven-plugin.version>
+        <flatten-maven-plugin.version>1.7.2</flatten-maven-plugin.version>
         <maven-surefire-plugin.version>3.5.3</maven-surefire-plugin.version>
         <maven-failsafe-plugin.version>3.5.3</maven-failsafe-plugin.version>
         <maven-source-plugin.version>3.3.1</maven-source-plugin.version>
         <maven-install-plugin.version>3.1.4</maven-install-plugin.version>
         <maven-deploy-plugin.version>3.1.4</maven-deploy-plugin.version>
         <maven-javadoc-plugin.version>3.11.2</maven-javadoc-plugin.version>
-        <maven-gpg-plugin.version>3.2.7</maven-gpg-plugin.version>
+        <maven-gpg-plugin.version>3.2.8</maven-gpg-plugin.version>
         <central-publishing-maven-plugin.version>0.8.0</central-publishing-maven-plugin.version>
 
         <!-- dependency versions -->