fix: d_numerator device

Author: kozistr

pytorch_optimizer/optimizer/prodigy.py

@@ -110,6 +110,8 @@ def step(self, closure: CLOSURE = None) -> LOSS:
 
         if 'd_numerator' not in group:
             group['d_numerator'] = torch.tensor([0.0], device=device)
+        elif group['d_numerator'].device != device:
+            group['d_numerator'] = group['d_numerator'].to(device)
 
         d_numerator = group['d_numerator']
         d_numerator.mul_(beta3)