Update gitea go-sdk to v0.15.0 (#385)

Update "code.gitea.io/sdk/gitea" to latest release

Reviewed-on: https://gitea.com/gitea/tea/pulls/385
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>
Co-committed-by: 6543 <6543@obermui.de>

vendor/code.gitea.io/sdk/gitea/list_options.go

@@ -26,8 +26,13 @@ func (o ListOptions) getURLQuery() url.Values {
 	return query
 }
 
-func (o ListOptions) setDefaults() {
-	if o.Page < 1 {
+// setDefaults set default pagination options if none or wrong are set
+// if you set -1 as page it will set all to 0
+func (o *ListOptions) setDefaults() {
+	if o.Page < 0 {
+		o.Page, o.PageSize = 0, 0
+		return
+	} else if o.Page == 0 {
 		o.Page = 1
 	}