[bugfix] Update GetURL to extract url from Link objects with href (#4249)

# Description

> If this is a code change, please include a summary of what you've coded, and link to the issue(s) it closes/implements.
>
> If this is a documentation change, please briefly describe what you've changed and why.

This pull request updates our parsing of the `url` property in incoming ActivityPub items to also include Link items, and not just bare URIs.

The first discovered url is still used as the *gtsmodel.Account or *gtsmodel.Status `url` property, so this change only really affects our dereference URL anti-spoof check thingy.

~~Should fix https://codeberg.org/superseriousbusiness/gotosocial/issues/4248 but I need to run it and test it myself first to be sure.~~

Fixes https://codeberg.org/superseriousbusiness/gotosocial/issues/4248

## Checklist

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If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

- [x] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [x] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [x] I/we have not leveraged AI to create the proposed changes.
- [x] I/we have performed a self-review of added code.
- [x] I/we have written code that is legible and maintainable by others.
- [x] I/we have commented the added code, particularly in hard-to-understand areas.
- [ ] I/we have made any necessary changes to documentation.
- [x] I/we have added tests that cover new code.
- [x] I/we have run tests and they pass locally with the changes.
- [x] I/we have run `go fmt ./...` and `golangci-lint run`.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4249
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Co-committed-by: tobi <tobi.smethurst@protonmail.com>

internal/typeutils/astointernal.go

@@ -268,10 +268,12 @@ func (c *Converter) ASStatusToStatus(ctx context.Context, statusable ap.Statusab
 	// status.URL
 	//
 	// Web URL of this status (optional).
-	if statusURL, err := ap.ExtractURL(statusable); err == nil {
-		status.URL = statusURL.String()
+	if statusURL := ap.GetURL(statusable); len(statusURL) != 0 {
+		// Take the first hit.
+		status.URL = statusURL[0].String()
 	} else {
-		status.URL = status.URI // Fall back to the URI.
+		// Fall back to the URI.
+		status.URL = status.URI
 	}
 
 	// status.Content