Upgrade to Maven 3.8.8

Closes gh-387

Author: wilkinsona

pom.xml

@@ -43,9 +43,9 @@
 		<gradle.version>3.4</gradle.version>
 		<groovy.version>2.4.21</groovy.version>
 		<log4j.version>2.17.1</log4j.version>
-		<maven-core.version>3.5.0</maven-core.version>
+		<maven-core.version>3.8.8</maven-core.version>
 		<maven-plugin-api.version>${maven-core.version}</maven-plugin-api.version>
-		<maven-plugin-annotations.version>3.5</maven-plugin-annotations.version>
+		<maven-plugin-annotations.version>3.8.2</maven-plugin-annotations.version>
 		<mockito.version>3.6.28</mockito.version>
 		<junit.version>5.8.1</junit.version>
 		<javassist.version>3.21.0-GA</javassist.version>