Bump jetty-server in /herddb-services (#806)

Bumps [jetty-server](https://github.com/eclipse/jetty.project) from 9.4.44.v20210927 to 9.4.51.v20230217.
- [Release notes](https://github.com/eclipse/jetty.project/releases)
- [Commits](jetty/jetty.project@jetty-9.4.44.v20210927...jetty-9.4.51.v20230217)

---
updated-dependencies:
- dependency-name: org.eclipse.jetty:jetty-server
  dependency-type: direct:production
...

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

herddb-services/pom.xml

@@ -30,7 +30,7 @@
     <packaging>jar</packaging>
     <properties>
         <buildTimestamp>${maven.build.timestamp}</buildTimestamp>
-        <jetty.version>9.4.44.v20210927</jetty.version>
+        <jetty.version>9.4.51.v20230217</jetty.version>
         <libs.jaxws.jaxb-api>2.3.0</libs.jaxws.jaxb-api>
         <libs.jaxws.jaxb-impl>2.3.0</libs.jaxws.jaxb-impl>
         <libs.javaxactivation.api>1.2.0</libs.javaxactivation.api>