Bump assertj-parent-pom from 2.2.7 to 2.2.8

Bumps [assertj-parent-pom](https://github.com/assertj/assertj-maven-parent-pom) from 2.2.7 to 2.2.8.
- [Release notes](https://github.com/assertj/assertj-maven-parent-pom/releases)
- [Commits](assertj/assertj-parent-pom@assertj-parent-pom-2.2.7...assertj-parent-pom-2.2.8)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pom.xml

@@ -10,7 +10,7 @@
     <parent>
         <groupId>org.assertj</groupId>
         <artifactId>assertj-parent-pom</artifactId>
-        <version>2.2.7</version>
+        <version>2.2.8</version>
     </parent>
 
     <scm>