Bump org.apache.maven:maven-core from 3.2.5 to 3.8.1

Bumps [org.apache.maven:maven-core](https://github.com/apache/maven) from 3.2.5 to 3.8.1.
- [Release notes](https://github.com/apache/maven/releases)
- [Commits](apache/maven@maven-3.2.5...maven-3.8.1)

---
updated-dependencies:
- dependency-name: org.apache.maven:maven-core
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pom.xml

@@ -116,7 +116,7 @@ under the License.
   <properties>
     <doxiaVersion>1.11.1</doxiaVersion>
     <doxiaSitetoolsVersion>1.11.1</doxiaSitetoolsVersion>
-    <mavenVersion>3.2.5</mavenVersion>
+    <mavenVersion>3.8.1</mavenVersion>
     <scmVersion>2.0.1</scmVersion>
     <aetherVersion>1.0.0.v20140518</aetherVersion>
     <sitePluginVersion>3.12.1</sitePluginVersion>