Bump io.vertx:vertx5-parent from 4 to 6 (#195)

Bumps io.vertx:vertx5-parent from 4 to 6.

---
updated-dependencies:
- dependency-name: io.vertx:vertx5-parent
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.vertx</groupId>
     <artifactId>vertx5-parent</artifactId>
-    <version>4</version>
+    <version>6</version>
   </parent>
 
   <modelVersion>4.0.0</modelVersion>