bug#44825: Error in reporting guix deploy error

[Christopher Lemmer Webber <cwebber@dustycloud.org>]

Seems strange... the message I get:

  guix deploy: error: failed to deploy tulsi: ~A: ~S

Errors upon errors!  Formatting this time, apparently. :)

Looking at the relevant code:

(define (deploy-machine* store machine)
  "Deploy MACHINE, taking care of error handling."
  (info (G_ "deploying to ~a...~%")
        (machine-display-name machine))

  (guard (c ((message-condition? c)
             (report-error (G_ "failed to deploy ~a: ~a~%")
                           (machine-display-name machine)
                           (condition-message c)))
            ((deploy-error? c)
             (when (deploy-error-should-roll-back c)
               (info (G_ "rolling back ~a...~%")
                     (machine-display-name machine))
               (run-with-store store (roll-back-machine machine)))
             (apply throw (deploy-error-captured-args c))))
    (run-with-store store (deploy-machine machine))

    (info (G_ "successfully deployed ~a~%")
          (machine-display-name machine))))

I looked at other examples of report-error, they seemed similar.. can't
see why this one wouldn't be formatting correctly.  Any idea?