Fix api_test.go under Go 1.20.

webserver/api_test.go

@@ -18,16 +18,20 @@ import (
 	"github.com/jech/galene/token"
 )
 
-var setupOnce = sync.OnceFunc(func() {
+var setupOnce sync.Once
-	Insecure = true
+
-	err := Serve("localhost:1234", "")
+func setup() {
-	if err != nil {
+	setupOnce.Do(func() {
-		panic("could not start server")
+		Insecure = true
-	}
+		err := Serve("localhost:1234", "")
-})
+		if err != nil {
+			panic("could not start server")
+		}
+	})
+}
 
 func setupTest(dir, datadir string) error {
-	setupOnce()
+	setup()
 
 	group.Directory = dir
 	group.DataDirectory = datadir