Bump org.apache.maven.plugins:maven-surefire-plugin from 3.5.5 to 3.5.6

Bumps [org.apache.maven.plugins:maven-surefire-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-surefire-plugin
  dependency-version: 3.5.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

api/pom.xml

diff --git a/api/pom.xml b/api/pom.xml
index 52c2154..d1963b9 100644
--- a/api/pom.xml
+++ b/api/pom.xml
@@ -164,7 +164,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>3.5.5</version>
+                <version>3.5.6</version>
             </plugin>
 
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