Support table styles for export PDF

[Gijsreyn]

Enhancement

While testing the new alpha release for Jupyter books, we noticed unusual formatting issues when exporting tables to PDF. This problem doesn't occur in Sphinx, as it supports table styles for PDF exports.

To make it successful and migrate to v2, we really would love to see table styles coming to MySTMD for PDF exports.

P.S. The documentation said the following indeed: Styles are Only for HTML CSS styles are currently only used for HTML outputs and are not carried through to all export targets (e.g. LaTeX) and are primarily used for web.