Enable linking release description files

It should be possible to add/link an additional release description file in another one so that those could be build at one run. e.g in Qt 6.2.2 release description file we could add a link to qtqmlscriptcompiler (https://codereview.qt-project.org/gitweb?p=qtsdk/tqtc-qtsdk.git;a=blob;f=packaging-tools/configurations/releases/release-addons-qt-qmlscriptcompiler-622.ini;h=22b181ed07bbc21d5f9a39a01d1a30c1e6815d13;hb=HEAD) and qtinterfaceframework (https://codereview.qt-project.org/gitweb?p=qtsdk/tqtc-qtsdk.git;a=blob;f=packaging-tools/configurations/releases/release-addons-qt-interfaceframework-622.ini;h=5cac4dbb33dfd90cfa2b1f90d18ddf1e1705c0f5;hb=HEAD) ones instead of adding all repositories directly (https://codereview.qt-project.org/c/qtsdk/tqtc-qtsdk/+/382033).