Path `docs/current` no longer returns latest/current version of docs

[cloudymax]

Quite a few places around the cnpg ecosystem reference "https://cloudnative-pg.io/docs/current/" which seems to have stopped working. Replacing current with a valid release eg: 1.28 will get you to a real page but otherwise you'll get a blank page.

Might be related to #21 since I've seen a few documentation/current/ occurrences as well.

Cheers!