Bump org.eclipse.jetty:jetty-server from 9.4.53.v20231009 to 12.0.6

Bumps org.eclipse.jetty:jetty-server from 9.4.53.v20231009 to 12.0.6.

---
updated-dependencies:
- dependency-name: org.eclipse.jetty:jetty-server
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

org.eclipse.lemminx/pom.xml

@@ -284,7 +284,7 @@
 			<groupId>org.eclipse.jetty</groupId>
 			<artifactId>jetty-server</artifactId>
 			<!-- Need to stick to 9.x as long as build is running with Java 1.8-->
-			<version>9.4.53.v20231009</version>
+			<version>12.0.6</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>