added a function that checks the output argument provided to the prog…

…ram to see if it was valid. This change had to be made because the out variable in the parser wasn't behaving right. This needs to be fixed in the future

src/ldsc/munge_sumstats/check_munge_args.py

@@ -0,0 +1,6 @@
+from typing import Any
+
+
+def check_munge_args(args: list[Any]) -> None:
+    if args.out is None:
+        raise ValueError("No output was specified")