Update XStream to version 1.4.20

build.gradle

@@ -49,7 +49,7 @@ project(":de.bmotionstudio.gef.editor") {
 	}
 
 	dependencies {
-		implementation group: "com.thoughtworks.xstream", name: "xstream", version: "1.4.19"
+		implementation group: "com.thoughtworks.xstream", name: "xstream", version: "1.4.20"
 		// Current versions of XStream depend on MXParser, but not any specific version of it.
 		// To avoid the version number changing unexpectedly and breaking the MANIFEST.MF classpath entries,
 		// hardcode a specific MXParser version here.

de.bmotionstudio.gef.editor/.classpath

@@ -9,5 +9,5 @@
 	<classpathentry kind="output" path="bin"/>
 	<classpathentry exported="true" kind="lib" path="lib/dependencies/mxparser-1.2.2.jar"/>
 	<classpathentry exported="true" kind="lib" path="lib/dependencies/xmlpull-1.1.3.1.jar"/>
-	<classpathentry exported="true" kind="lib" path="lib/dependencies/xstream-1.4.19.jar"/>
+	<classpathentry exported="true" kind="lib" path="lib/dependencies/xstream-1.4.20.jar"/>
 </classpath>

de.bmotionstudio.gef.editor/META-INF/MANIFEST.MF

@@ -151,7 +151,7 @@ Export-Package: de.bmotionstudio.gef.editor;
 Bundle-ClassPath: .,
  lib/dependencies/mxparser-1.2.2.jar,
  lib/dependencies/xmlpull-1.1.3.1.jar,
- lib/dependencies/xstream-1.4.19.jar,
+ lib/dependencies/xstream-1.4.20.jar,
  lib/ext/groovy-2.0.5.jar,
  lib/ext/asm-4.0.jar,
  lib/ext/antlr-2.7.7.jar