guix package, pull: Use 'with-build-handler'.

guix package, pull: Use 'with-build-handler'.

* guix/scripts/package.scm (build-and-use-profile): Remove #:dry-run?
and #:use-substitutes?.  Remove call to 'show-what-to-build' and
'dry-run?' special case.
(process-actions): Adjust accordingly.
(guix-package*): Wrap 'parameterize' in 'with-build-handler'.
* guix/scripts/pull.scm (build-and-install): Remove #:use-substitutes?
and #:dry-run? and adjust 'update-profile' call accordingly.  Remove
'dry-run?' conditional.
(guix-pull): Wrap body in 'with-build-handler'.