FIX: Estimate free memory with available, not free

Author: mgxd

nibabies/config.py

@@ -143,7 +143,7 @@
 try:
     from psutil import virtual_memory
 
-    _free_mem_at_start = round(virtual_memory().free / 1024**3, 1)
+    _free_mem_at_start = round(virtual_memory().available / 1024**3, 1)
 except Exception:
     _free_mem_at_start = None