Bump assertj-core from 3.13.0 to 3.13.1

Bumps [assertj-core](https://github.com/joel-costigliola/assertj-core) from 3.13.0 to 3.13.1.
- [Release notes](https://github.com/joel-costigliola/assertj-core/releases)
- [Commits](assertj/assertj@assertj-core-3.13.0...assertj-core-3.13.1)

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

pom.xml

@@ -64,7 +64,7 @@
 
         <junit.version>4.12</junit.version>
         <junit5.version>5.5.1</junit5.version>
-        <assertj.version>3.13.0</assertj.version>
+        <assertj.version>3.13.1</assertj.version>
         <mockito.version>3.0.0</mockito.version>
     </properties>