Fixed wandb logging for learning rate.

src/train.py

@@ -137,7 +137,7 @@ def train_pipleine(args):
                 # Report metrics every 4 batches
                 if ((batch_ct + 1) % 4) == 0:
                     # Log epoch and loss
-                    wandb.log({'epoch': epoch, 'loss': loss, 'lr': lr_scheduler.get_last_lr()}, step=batch_ct)
+                    wandb.log({'epoch': epoch, 'loss': loss, 'lr': lr_scheduler.get_last_lr()[0]}, step=batch_ct)
                     print(f"Epoch {epoch}, Batch {i}, Loss after {str(batch_ct)} batches: {loss:.3f},"
                           f" Batch time: {time_elapsed:.4f}, lr: {lr_scheduler.get_last_lr()[0]:.3f}")