test: answer 2nd mdadm --create question for compat with new version

test: answer 2nd mdadm --create question for compat with new version

New version of mdadm now asks a second question, so send 'y' twice
to it in the test scripts

[    5.253483] TEST-64-UDEV-STORAGE.sh[684]: + echo y
[    5.254412] TEST-64-UDEV-STORAGE.sh[685]: + mdadm --create /dev/md/mdmirror --name mdmirror --uuid aaaaaaaa:bbbbbbbb:cccccccc:00000001 /dev/disk/by-id/scsi-0systemd_foobar_deadbeefmdadm0 /dev/disk/by-id/scsi-0systemd_foobar_deadbeefmdadm1 -v -f --level=1 --raid-devices=2
[    5.254759] TEST-64-UDEV-STORAGE.sh[685]: To optimalize recovery speed, it is recommended to enable write-indent bitmap, do you want to enable it now? [y/N]? mdadm: Note: this array has metadata at the start and
[    5.255085] TEST-64-UDEV-STORAGE.sh[685]:     may not be suitable as a boot device.  If you plan to
[    5.255418] TEST-64-UDEV-STORAGE.sh[685]:     store '/boot' on this device please ensure that
[    5.255745] TEST-64-UDEV-STORAGE.sh[685]:     your boot-loader understands md/v1.x metadata, or use
[    5.256285] TEST-64-UDEV-STORAGE.sh[685]:     --metadata=0.90
[    5.256672] TEST-64-UDEV-STORAGE.sh[685]: mdadm: size set to 64512K
[    5.257063] TEST-64-UDEV-STORAGE.sh[685]: Continue creating array [y/N]? mdadm: create aborted.

This is backward compatible with the older version that asks just one
question