Fix broken anchor links in BIP 0342, BIP 0022, BIP 0023

[EthanHeilman]

At some point github changed how anchor links work. Currently anchor links using the double square bracket format require that the anchor be prepended with user-content-.

This means that the following link used to work, but doesn't today

 [[bip-0341.mediawiki#design|BIP341]]

The link that works today would be

[[bip-0341.mediawiki#user-content-design|BIP341]]

The link still resolves to the page, but just not the anchor so I suspect no one noticed.

In addition to this it appears that in the past github anchors could have spaces or punction, but that is no longer valid. Spaces are replaced with _ and punction appears to be not included in the anchor.

I fixed this for BIP 0342, BIP 0022, BIP 0023, but it impacts a good chunk of BIPs. If you want I can change this PR to fix for all the BIPs, but I didn't want to put in the time to do that in case an editor wanted to make these changes themselves.

If this PR isn't useful or the project isn't interested in fixing this very minor linking issue. Feel free to close this PR.

[murchandamus]

I was able to verify the issue (original links are broken, new link works in the edited file). Will follow-up in the following days.