Bump groovy-all from 2.4.8 to 2.4.21

Bumps [groovy-all](https://github.com/apache/groovy) from 2.4.8 to 2.4.21.
- [Release notes](https://github.com/apache/groovy/releases)
- [Commits](https://github.com/apache/groovy/commits)

---
updated-dependencies:
- dependency-name: org.codehaus.groovy:groovy-all
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

pom.xml

@@ -72,7 +72,7 @@
     <maven.resources.plugin.version>3.1.0</maven.resources.plugin.version>
     <maven.source.plugin.version>3.0.1</maven.source.plugin.version>
     <groovy.maven.plugin.version>2.1.1</groovy.maven.plugin.version>
-    <groovy.all.version>2.4.8</groovy.all.version>
+    <groovy.all.version>2.4.21</groovy.all.version>
     <keytool.maven.plugin.version>1.5</keytool.maven.plugin.version>
     <build.helper.maven-plugin.version>1.12</build.helper.maven-plugin.version>
     <maven.compiler.plugin.version>3.8.1</maven.compiler.plugin.version>