Bump jetty.version from 9.4.19.v20190610 to 9.4.30.v20200611 in /core

Bumps `jetty.version` from 9.4.19.v20190610 to 9.4.30.v20200611.

Updates `jetty-server` from 9.4.19.v20190610 to 9.4.30.v20200611
- [Release notes](https://github.com/eclipse/jetty.project/releases)
- [Commits](https://github.com/eclipse/jetty.project/compare/jetty-9.4.19.v20190610...jetty-9.4.30.v20200611)

Updates `jetty-servlet` from 9.4.19.v20190610 to 9.4.30.v20200611
- [Release notes](https://github.com/eclipse/jetty.project/releases)
- [Commits](https://github.com/eclipse/jetty.project/compare/jetty-9.4.19.v20190610...jetty-9.4.30.v20200611)

Updates `jetty-webapp` from 9.4.19.v20190610 to 9.4.30.v20200611
- [Release notes](https://github.com/eclipse/jetty.project/releases)
- [Commits](https://github.com/eclipse/jetty.project/compare/jetty-9.4.19.v20190610...jetty-9.4.30.v20200611)

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

Closes #91

Change-Id: I798b55646d8dcda61fd75118cf7086ba57b25122
diff --git a/core/pom.xml b/core/pom.xml
index 20dd23d..69cc0e0 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -10,7 +10,7 @@
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<spring.version>5.2.7.RELEASE</spring.version>
 		<jersey.version>1.19.4</jersey.version>
-		<jetty.version>9.4.19.v20190610</jetty.version>
+		<jetty.version>9.4.30.v20200611</jetty.version>
 		<hibernate.version>5.3.7.Final</hibernate.version>
 		<log4j.version>2.13.3</log4j.version>
 	</properties>