fdo#82969 add global shortcut for autospellcheck

Change-Id: I02b933ac2080ddb46b06a525a0304833ec28acf8
Reviewed-on: https://gerrit.libreoffice.org/13088
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>
(cherry picked from commit 51a572f218cb49e2c3aabdc7e6a7dc47e56c4ded)
Reviewed-on: https://gerrit.libreoffice.org/13119
Reviewed-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>
Tested-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>