fdo#75757: remove inheritance to std::vector

Change-Id: I17b1057c2551f41b15547d7563434e3344ab6be8
Reviewed-on: https://gerrit.libreoffice.org/11822
Reviewed-by: David Tardon <dtardon@redhat.com>
Tested-by: David Tardon <dtardon@redhat.com>