Bump junit from 4.12 to 4.13.1 in /contrib

Bumps [junit](https://github.com/junit-team/junit4) from 4.12 to 4.13.1.
- [Release notes](https://github.com/junit-team/junit4/releases)
- [Changelog](https://github.com/junit-team/junit4/blob/main/doc/ReleaseNotes4.12.md)
- [Commits](junit-team/junit4@r4.12...r4.13.1)

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

Author: dependabot[bot]

contrib/pom.xml

@@ -67,7 +67,7 @@
         <spring.version>4.2.0.RELEASE</spring.version>
 
         <!-- Test Dependency Versions -->
-        <junit.version>4.12</junit.version>
+        <junit.version>4.13.1</junit.version>
         <assertj.version>3.6.2</assertj.version>
         <commons-lang.version>2.6</commons-lang.version>
         <awaitility.version>2.0.0</awaitility.version>