gce: don't terminate instances on migration
gce: don't terminate instances on migration

Seems to be working without termination.

xairy/syzkaller,hyz0906/syzkaller,zoulasc/syzkaller,hyz0906/syzkaller,google/syzkaller,xairy/syzkaller,zoulasc/syzkaller,hyz0906/syzkaller,xairy/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,zoulasc/syzkaller,hyz0906/syzkaller,xairy/syzkaller,dotweiba/syzkaller,google/syzkaller,hyz0906/syzkaller,google/syzkaller,dotweiba/syzkaller,zoulasc/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,dotweiba/syzkaller,xairy/syzkaller,dotweiba/syzkaller