Usa a stable Zola release

[senekor]

We are currently using a fork, because we rely on a few patches on top of Zola. Ideally these (or an alternative that suits us) can be upstreamed. This issue is to keep track of the upstreaming progress.

The version of zola we install is a specific commit hash. That commit merges all patches we rely on and has a summary of them all as its commit message: senekor/zola@620bf3c

At this point, all patches are merged, but we're still waiting on a new release of zola.

⏳️ Merged, but not yet released:

• Alias: preserve the hash when redirecting
  • currently used patch: senekor/zola@2e63e41
  • merged PR: Alias: preserve the hash when redirecting getzola/zola#2851
• Allow generating empty feeds (applies to our inside-rust/releases.json)
  • currently used patch: senekor/zola@f4c69f8
  • merged PR: Allow generating empty feeds getzola/zola#2850
• Allow us to sort pages by their permalink (which is effectively sorting by date, because the permalink of each post starts with its date of publication)
  • currently used patch: senekor/zola@fe820e3
  • merged PR: Add permalink sorting getzola/zola#2857
• Enable rendering our releases.json feed
  • currently used patch: senekor/zola@f813dee
  • merged PR: Allow json and ics templates for custom feeds getzola/zola#2856

🔧 Not planned for upstreaming

• Remove dependency on onig: senekor/zola@d045299
  (The onig dependency used to fail the build of Zola in some environments, this is now fixed upstream.)