post-upload: Upload Linux source to artifacts dir

The source from the Linux build is desireable as it has permissions and
line endings set correctly.

.ci/scripts/common/post-upload.sh

@@ -11,6 +11,7 @@ if [[ -z "${NO_SOURCE_PACK}" ]]; then
   git clone --depth 1 file://$(readlink -e .) ${REV_NAME}-source
   tar -cJvf "${REV_NAME}-source.tar.xz" ${REV_NAME}-source
   cp -v "${REV_NAME}-source.tar.xz" "$DIR_NAME"
+  cp -v "${REV_NAME}-source.tar.xz" "${ARTIFACTS_DIR}/"
 fi
 
 tar $COMPRESSION_FLAGS "$ARCHIVE_NAME" "$DIR_NAME"