[hailctl dataproc] Print all gcloud args in hailctl dataproc modify

[nawatts]

Currently, the hailctl dataproc modify does not print the first (after the cluster name) argument to gcloud dataproc clusters update. This bug was introduced in #9078.

For example:

$ hailctl dataproc modify some-cluster --num-workers 2 --dry-run
gcloud dataproc clusters update some-cluster \

With this change, the --num-workers argument is printed.

$ hailctl dataproc modify some-cluster --num-workers 2 --dry-run
gcloud dataproc clusters update some-cluster \
    --num-workers=2