Create a repo redirect when transferring ownership (#6210) (#6211)

When transferring ownership of a repo to a different user/org,
create a repo redirect that points to the new location in the same
way that is done when a repo is renamed.

Signed-off-by: James E. Blair <jeblair@redhat.com>

modules/context/repo.go

@@ -204,7 +204,7 @@ func RedirectToRepo(ctx *Context, redirectRepoID int64) {
 	redirectPath := strings.Replace(
 		ctx.Req.URL.Path,
 		fmt.Sprintf("%s/%s", ownerName, previousRepoName),
-		fmt.Sprintf("%s/%s", ownerName, repo.Name),
+		fmt.Sprintf("%s/%s", repo.MustOwnerName(), repo.Name),
 		1,
 	)
 	ctx.Redirect(redirectPath)