Bump hk2.version from 2.6.1 to 3.1.0

Bumps `hk2.version` from 2.6.1 to 3.1.0.

Updates `org.glassfish.hk2:hk2-locator` from 2.6.1 to 3.1.0
- [Release notes](https://github.com/eclipse-ee4j/glassfish-hk2/releases)
- [Changelog](https://github.com/eclipse-ee4j/glassfish-hk2/blob/master/CHANGELOG)
- [Commits](https://github.com/eclipse-ee4j/glassfish-hk2/commits)

Updates `org.glassfish.hk2:hk2-metadata-generator` from 2.6.1 to 3.1.0

---
updated-dependencies:
- dependency-name: org.glassfish.hk2:hk2-locator
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.glassfish.hk2:hk2-metadata-generator
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

pom.xml

@@ -144,7 +144,7 @@
     <zookeeper.version>3.9.2</zookeeper.version>
     <async-http-client.version>2.12.3</async-http-client.version>
     <jersey.version>2.42</jersey.version>
-    <hk2.version>2.6.1</hk2.version>
+    <hk2.version>3.1.0</hk2.version>
     <javassist.version>3.30.2-GA</javassist.version>
     <swagger.version>1.6.14</swagger.version>
     <swagger-ui.version>5.17.0</swagger-ui.version>