Use busybox dd in system-device-sharing.yaml

Signed-off-by: MN Nithin <MN.Nithin@in.bosch.com>

test-cases/tiny-container-system-device-sharing.yaml

@@ -30,7 +30,7 @@ run:
     - "# Ensure we have loop device:"
     - modprobe loop
     - "# Create the random file and map it to loop0 device on host:"
-    - dd if=/dev/urandom of=/var/test.img bs=1M count=1
+    - busybox dd if=/dev/urandom of=/var/test.img bs=1M count=1
     - losetup /dev/loop0 /var/test.img
     - "# Check that a simple loop device created on the host can be shared with the container and accessed from inside it:"
     - lavatests/test-device-sharing --ospack "$OSPACK" -t lxc/lxc-tiny-connectivity --aa-namespace "lxc-apertis-tiny-system"