build(deps-dev): bump org.apache.maven.plugins:maven-failsafe-plugin (#1764)

Bumps [org.apache.maven.plugins:maven-failsafe-plugin](https://github.com/apache/maven-surefire) from 3.5.5 to 3.5.6.
- [Release notes](https://github.com/apache/maven-surefire/releases)
- [Commits](https://github.com/apache/maven-surefire/compare/surefire-3.5.5...surefire-3.5.6)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-failsafe-plugin
  dependency-version: 3.5.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

apps/showcase/pom.xml

@@ -167,7 +167,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-failsafe-plugin</artifactId>
-                <version>3.5.5</version>
+                <version>3.5.6</version>
                 <configuration>
                     <includes>
                         <include>it.org.apache.struts2.showcase.*Test</include>