Bump groovy from 2.4.15 to 2.5.8

Bumps [groovy](https://github.com/apache/groovy) from 2.4.15 to 2.5.8.
- [Release notes](https://github.com/apache/groovy/releases)
- [Commits](https://github.com/apache/groovy/commits)

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

pom.xml

@@ -34,7 +34,7 @@
         <dependency>
             <groupId>org.codehaus.groovy</groupId>
             <artifactId>groovy</artifactId>
-            <version>2.4.15</version>
+            <version>2.5.8</version>
             <scope>test</scope>
         </dependency>
         <dependency>