Label was really not changed because of fix by commit
2f2730bc77c972d613cfec421468c84f15749708.
UUID is different due to fact that ISO image does not have UUID and
libblkid generate one from compilation date. Plus "Joliet Extension" in UDF
context does not make sense.
-ID_FS_APPLICATION_ID=GENISOIMAGE ISO 9660/HFS FILESYSTEM CREATOR (C) 1993 E.YOUNGDALE (C) 1997-2006 J.PEARSON/J.SCHILLING (C) 2006-2007 CDRKIT TEAM
ID_FS_LABEL=test-udf
ID_FS_LABEL_ENC=test-udf
ID_FS_LOGICAL_VOLUME_ID=test-udf
-ID_FS_SYSTEM_ID=LINUX
ID_FS_TYPE=udf
ID_FS_USAGE=filesystem
-ID_FS_UUID=2008-02-05-12-29-20-00
-ID_FS_UUID_ENC=2008-02-05-12-29-20-00
-ID_FS_VERSION=Joliet\x20Extension
+ID_FS_UUID=47A83A8000000000
+ID_FS_UUID_ENC=47A83A8000000000
ID_FS_VOLUME_ID=test-udf
ID_FS_VOLUME_SET_ID=47A83A8000000000