cache(gha): don't require url attr if url_v2 is set

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

Author: crazy-max

cache/remotecache/gha/gha.go

@@ -63,10 +63,6 @@ func getConfig(attrs map[string]string) (*Config, error) {
 	if !ok {
 		scope = "buildkit"
 	}
-	url, ok := attrs[attrURL]
-	if !ok {
-		return nil, errors.Errorf("url not set for github actions cache")
-	}
 	token, ok := attrs[attrToken]
 	if !ok {
 		return nil, errors.Errorf("token not set for github actions cache")
@@ -80,12 +76,19 @@ func getConfig(attrs map[string]string) (*Config, error) {
 		}
 		apiVersionInt = int(i)
 	}
+	var url string
 	if apiVersionInt != 1 {
 		if v, ok := attrs[attrURLV2]; ok {
 			url = v
 			apiVersionInt = 2
 		}
 	}
+	if v, ok := attrs[attrURL]; ok && url == "" {
+		url = v
+	}
+	if url == "" {
+		return nil, errors.Errorf("url not set for github actions cache")
+	}
 	// best effort on old clients
 	if apiVersionInt == 0 {
 		if strings.Contains(url, "results-receiver.actions.githubusercontent.com") {