[clang-tools-extra] [Clang-doc] Display enum comments in HTML (PR #183085)

[Samrudh Nelli via cfe-commits]

SamrudhNelli wrote:

> Thanks for shrinking this down to be more minimal. Its definitely helped. One thing I'm realizing after looking at this locally is that there are no JSON tests for the new data. Please add those, since I think that's where the bug is likely to be. Right now we're trying to figure out what's wrong based on the post processed output, but I think its in a bad state even before that.

Added a line of `JSON-INDEX:      "TextComment": " Comment 1"`, since this test is passes, we know that there is no problem with the JSON.
Will remove this line before the final merge.

https://github.com/llvm/llvm-project/pull/183085