Update dependency org.codehaus.mojo:exec-maven-plugin to v3

Author: renovate[bot]

pom.xml

@@ -60,7 +60,7 @@
         <maven-javadoc.plugin.version>3.12.0</maven-javadoc.plugin.version>
         <maven-gpg.plugin.version>3.2.8</maven-gpg.plugin.version>
         <maven-compiler.plugin.version>3.14.1</maven-compiler.plugin.version>
-        <maven-exec.plugin.version>1.6.0</maven-exec.plugin.version>
+        <maven-exec.plugin.version>3.6.3</maven-exec.plugin.version>
     </properties>
 
     <dependencies>