Bump jetty-server in /OWLTools-Web

Bumps [jetty-server](https://github.com/eclipse/jetty.project) from 7.5.4.v20111024 to 9.4.17.v20190418.
- [Release notes](https://github.com/eclipse/jetty.project/releases)
- [Commits](jetty/jetty.project@jetty-7.5.4.v20111024...jetty-9.4.17.v20190418)

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

OWLTools-Web/pom.xml

@@ -35,7 +35,7 @@
 		<dependency>
 			<groupId>org.eclipse.jetty</groupId>
 			<artifactId>jetty-server</artifactId>
-			<version>7.5.4.v20111024</version>
+			<version>9.4.17.v20190418</version>
 		</dependency>
 	</dependencies>
 </project>