Adding tags around links is unnecessary and messes up GitHub formatting

[CyanoKobalamyne]

GitHub automatically linkifies strings that look like links. However, spr currently adds explicit <a> tags around links, which messes up the formatting for e.g. Markdown links like this that are in a list.

[leoluk]

This exists because we used to put the commit message into a code area to preserve formatting, requiring separate linkify.

Looks like the code area was removed but the linkify is still there. We can just remove that too now...