Allow empty flavor

Author: ByteOtter

src/gardenlinux/features/__main__.py

@@ -118,7 +118,7 @@ def main() -> None:
 
     additional_filter_func = lambda node: node not in args.ignore
 
-    if flavor is None or "":
+    if flavor is None:
         raise RuntimeError("Flavor could not be determined")
 
     if args.type == "arch":