Fix inaccessible anchors

[pilleye]

We need our frontend to be accessible to individuals with disabilities, including blindness or hearing loss. Make changes to our codebase to conform with standards that make it easier for those individuals to use our technology.

[fishdev]

Specifically, the anchors without a valid href attribute must be converted into buttons. It is worth noting that these fixes are mainly just to keep the linter from complaining as HTML5 has added support for placeholder hyperlinks.

[pilleye]

Is that the only accessibility change that we need? Or are there other ones that would help users?

[fishdev]

There are certainly other ways to improve accessibility but those should be proposed in separate issues. For example, see #15.