Relese hash/sig file have wrong key URL

[JedMeister]

A user has just reported:

attempting to check the download (of the hash-file) I followed the recipe in your docs for verifying.

First the retrieval of the key:

$ curl https://raw.githubusercontent.com/turnkeylinux/common/master/keys/tkl-bookworm-images.asc > tkl-bookworm-key

Then, the content of the downloaded "key-file" showed up:

$ cat tkl-bookworm-key 404: Not Found

That is because we include the wrong URL in the hash/sig file. It should be:

https://raw.githubusercontent.com/turnkeylinux/common/18.x/keys/tkl-bookworm-images.asc

Note the branch is 18.x - not master. I need to update the file, but as a workaround (for existing releases) I will also commit the key to the master branch so it will work.