Removes the Vale alt text rule
What does this MR do and why?
This MR removes the recently introduced Vale rule AltText.yml
in favour of https://github.com/DavidAnson/markdownlint/blob/main/doc/Rules.md#md045---images-should-have-alternate-text-alt-text, which is already in-use.
Resolves this Slack conversation: https://gitlab.slack.com/archives/C011GQM684V/p1721260188972789
Edited by Lysanne Pinto