REQIF13 — driver.xsd mistakenly references Tables XHTML module, instead of Basic Tables XHTML module

Clause 10.8.20. mentions the XHTML modules that need to be supported.

Among them is the so called "XHTML Basic Tables Module".
In comparison with the "XHTML Tables Module" that exists as well, it contains less XHTML elements for tables.

The choice to list only the XHTML Basic Tables module was intentional.
The intention was to simplify the development of ReqIF importing tools, especially if the target requirements authoring tool is not web based.

The standard ReqIF XML schema for inclusion of XHTML is driver.xsd.
However, driver.xsd mistakenly references the XHTML Tables Module.

Proposal: fix this by adapting the driver.xsd. This should be a one-line change.
This will establish consistency with the ReqIF standard document.