webui: recognize AsciiDoc files as valid text files (#16850)
* webui: recognize AsciiDoc files as valid text files
* webui: add an updated static webui build
* webui: add the updated dependency list
* webui: re-add an updated static webui build
This also reverts commit 742dbb837939c176a813868c268d28ebd3fafb7c.
