Update Firefox data for char attributes of HTML element

[queengooborg]

This PR updates and corrects version values for Firefox and Firefox Android for the char and charoff attributes of various HTML elements. The data comes from the mdn-bcd-collector project (v10.6.5).

Check out the collector's guide on how to review this PR.

Tests Used: https://mdn-bcd-collector.gooborg.com/tests/html/elements/col/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/colgroup/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/tbody/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/td/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/tfoot/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/th/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/thead/char https://mdn-bcd-collector.gooborg.com/tests/html/elements/tr/char

[teoli2003]

So, why the implementation comment?

[queengooborg]

The impl_url is just something to track bugs, commits, etc. for when the feature was implemented -- they're not meant to be an indication of an issue with the feature, so no harm in leaving them, but also no harm in removing them either!

[Elchi3]

That impl bug is still open, though?