Support annotated tags when using create release API

[kemzeb]

This adds a new field, "tag_message", that represents the message of the annotated tag.

Resolves #31835.

[kemzeb]

Currently we don't return the tag message in the response. We don't store the tag message in the Release model, so that would mean we would have to either:

• Communicate to git in order to get this
• Store the tag message in the database
• Don't include it in the response

I looked to see what the other forges were doing, and it appears that GitLab doesn't expose a similar field in its API response. See here.

[lunny]

How about reuse body as tag message? This is a non-compatible API change with Github API v3 https://docs.github.com/en/rest/releases/releases?apiVersion=2022-11-28#create-a-release

[kemzeb]

Done, though the problems I see with this is that:

• Both the release note and the tag message will be the same
• You can't create lightweight tags if you have a release note

Not sure if these are potential problems

[lunny]

Looks like Github API doesn't support to create tag.

[lunny]

I noticed in web router, the msg is

		msg := ""
		if len(form.Title) > 0 && form.AddTagMsg {
			msg = form.Title + "\n\n" + form.Content
		}

Which has a different implementation between web and this API.

[kemzeb]

I'm still not sure if its desirable to have both the tag message and the release description be the same. I also experimented with the GitHub API, and there really doesn't seem to be a way to create an annotated tag with this endpoint (even when specifying the body field).

This does look like it has been a sought after feature though.