misc/py-spdx-tools: Fix fs-violations for consumers

When run as root by a consumer port, spdx_tools writes several files to
$PYTHON_SITELIB}/spdx_tools/spdx/parser/ that must be pregenerated to
avoid fs-violations in poudriere.

Pass maintainership to kde@ since the main consumers of this will be the
Qt6 ports starting with Qt 6.11.0.

PR: 294345
Approved by: kai
MFH: 2026Q2