Bump junit from 4.12 to 4.13.1 in /gwt-editor-gwt2-tests

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] <[email protected]>

Author: dependabot[bot]

gwt-editor-gwt2-tests/pom.xml

@@ -19,7 +19,7 @@
         <maven.gwt.plugin>1.0.0</maven.gwt.plugin>
 
         <gwt.version>2.9.0</gwt.version>
-        <junit.version>4.12</junit.version>
+        <junit.version>4.13.1</junit.version>
     </properties>
 
     <dependencies>