Remove useless include tools/debug.hxx from forms and extensions

Change-Id: Idc8ecbb65c7c4c63950d8b249e0d0d91788d6d3b
Reviewed-on: https://gerrit.libreoffice.org/11012
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>
Tested-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>