Fix LR schedulers when optimizers with frequencies

Author: milesial

src/pytorch_lightning/loops/epoch/training_epoch_loop.py

@@ -390,7 +390,7 @@ def update_lr_schedulers(self, interval: str, update_plateau_schedulers: bool) -
         if interval == "step" and self._should_accumulate():
             return
         active_optimizers = _get_active_optimizers(
-            self.trainer.optimizers, self.trainer.optimizer_frequencies, self.total_batch_idx
+            self.trainer.optimizers, self.trainer.optimizer_frequencies, self.batch_idx
         )
         self._update_learning_rates(
             interval=interval,

tests/tests_pytorch/trainer/optimization/test_optimizers.py

@@ -286,7 +286,7 @@ def configure_optimizers(self):
             (dict(step_size=5), dict(T_max=2)),
             ("epoch", "epoch"),
             (5, 10),
-            (2, 3),
+            (4, 1),
             3,
         ),
     ],