fdo#74104 fdo#73904 backport Message dialog creation from message strings

Original title:
"allow simple MessageDialogs to be created from just message strings"

Commit 9b6b03542df7f6b0feecf60a13bab7e885ef3587 upgraded
sd/source/ui/view/Outliner.cxx to use a MessageDialog created from just a
message string, but was done before the existence of this commit -- it's
presumably safest to backport this commit to ensure that any other such
changed dialogs will work as expected.

(cherry picked from commit 257d1f4ff3094a42952663d620d7c49e3e7c747f)

Conflicts:
	basctl/source/basicide/moduldl2.cxx

Change-Id: I9f8324d1c61bd55ccc78e67699ebdfa946e48af6
Reviewed-on: https://gerrit.libreoffice.org/7859
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>