Always save global database if doesn't exist

Bot database doesn't have any crucial info to save, but global database is used at least with its ASF identifier (that we don't really want to regenerate) as well as for first run detection.

ArchiSteamFarm/GlobalDatabase.cs

@@ -102,7 +102,11 @@ namespace ArchiSteamFarm {
 			}
 
 			if (!File.Exists(filePath)) {
-				return new GlobalDatabase(filePath);
+				GlobalDatabase result = new(filePath);
+
+				Utilities.InBackground(result.Save);
+
+				return result;
 			}
 
 			GlobalDatabase globalDatabase;