I think this is the interface I want for uploading release files. There is an extra option to create the release ahead of the upload just in case it doesn't exist. One *should* create it with the create command or through the Gitea GUI so that everything can be properly written into the release info.
Owner and repo are combined into one string the same way Go dependencies or GitHub Actions are named. `<owner>/<repo>`
Each will be fetched from a matching environment variable if not specified on the command line.
The API token is read from the environment variable `RELEASE_KEY_GITEA`.
"GITEA" is on the end because Gitea itself will refuse to allow users to
configure Act variables starting with the name "GITEA_".
All information about the release is hard-coded right now. I just needed
to see it hit the API and appear on the Gitea page. Hooking up the extra
options is up next.
