disk-rootfs-fsck: Set type to sanity

This test is run as part of the sanity checks.

Setting the type to sanity allows the generate-jobs script to know that
this test is not supposed to be in any group and can be ignored when
generating job files.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>

test-cases/disk-rootfs-fsck.yaml

@@ -9,7 +9,7 @@ metadata:
   image-deployment:
     - APT
     - OSTree
-  type: functional
+  type: sanity
   exec-type: automated
   priority: high
   maintainer: "Apertis Project"