Bump xstream from 1.3.1 to 1.4.15 in /rm-skeleton#56

dependabot[bot] wants to merge 1 commit intomasteropenEHR/java-libs:masterfrom

dependabot/maven/rm-skeleton/com.thoughtworks.xstream-xstream-1.4.15openEHR/java-libs:dependabot/maven/rm-skeleton/com.thoughtworks.xstream-xstream-1.4.15Copy head branch name to clipboard