Bump ognl from 3.2.18 to 3.2.21

Bumps [ognl](https://github.com/jkuhnert/ognl) from 3.2.18 to 3.2.21.
- [Release notes](https://github.com/jkuhnert/ognl/releases)
- [Commits](https://github.com/jkuhnert/ognl/commits)

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index c43cee1..5821520 100644
--- a/pom.xml
+++ b/pom.xml
@@ -213,7 +213,7 @@
     <dependency>
       <groupId>ognl</groupId>
       <artifactId>ognl</artifactId>
-      <version>3.2.18</version>
+      <version>3.2.21</version>
       <scope>test</scope>
     </dependency>
   </dependencies>