Bump junit from 4.12 to 4.13.1

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](https://github.com/junit-team/junit4/compare/r4.12...r4.13.1)

---
updated-dependencies:
- dependency-name: junit:junit
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index ebb7c64..db0804a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -16,7 +16,7 @@
         <sentinel.version>1.6.0</sentinel.version>
         <apache.dubbo.version>2.7.22</apache.dubbo.version>
 
-        <junit.version>4.12</junit.version>
+        <junit.version>4.13.1</junit.version>
         <mockito.version>2.21.0</mockito.version>
     </properties>