fdo#73389 Writer does not show a docx-document with nested table correctly

The table manager can work with more table simultaneously
and so m_aCellWidths contains more table's properties.Only one
item of it belongs to the current table (getCurrentCellwidths).
Regression from 74c5ed19f430327988194cdcd6bdff09591a93fa

(cherry picked from commit d0c383256ef72d5212d8e2db77582d0ebe417209)

Conflicts:
	sw/qa/extras/ooxmlimport/ooxmlimport.cxx

Change-Id: I93efac0c004af1b2524c955ffb20c3ecd74a2920
Reviewed-on: https://gerrit.libreoffice.org/7543
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Miklos Vajna <vmiklos@collabora.co.uk>