Escape html tag in equations about doc-gen4

[xubaiw]

Screenshot from earlier 7d43c83 build.

[hargoniX]

The small stuff is not generated by doc-gen itself @xubaiw, the issue here is that your input files such as UCD/NameList.txt in your Unicode package do contain HTML tags, since you are statically including this into your code the generated equations will in turn contain these tags as well which causes this visual bug.

This basically comes down to: If your equations contain HTML in a way that the browser can interpret as syntactically correct your stuff will be represented in a wrong way. I'm guessing this can be fixed by escaping stuff here but I'm entirely unsure how to do this.

[hargoniX]

An alternative could be a an attribute that explicitly tells doc-gen to not generate equations about the declaration that is about to follow. This would also be reasonable in some regions of Mathlib where the equations that are generated are just insanely huge and not helpful at all like e.g. here: https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/BinaryHeap.html#BinaryHeap.heapifyDown