Updated regex to match cell content inside '<w:t>' even if <w:t> has XML
attributes such as 'xml:space="preserve"'. Updated test to have this kind
of '<w:t>'.
Updated regex pattern to make '{% vm %}' replace a two-step process:
- Search for <w:tc>...{% vm %}...</w:tc>;
- Parse table cell and put jinja tags inside correct places.
