Fix LTS test.

Author: Victarry

tests/unit_tests/test_layer_wise_optimizer.py

@@ -12,6 +12,7 @@
 from megatron.core.distributed import DistributedDataParallel, DistributedDataParallelConfig
 from megatron.core.optimizer import OptimizerConfig, get_megatron_optimizer
 from megatron.core.optimizer.layer_wise_optimizer import LayerWiseDistributedOptimizer
+from megatron.core.optimizer.muon import HAVE_EMERGING_OPTIMIZERS
 from megatron.core.optimizer.optimizer import Float16OptimizerWithFloat16Params, FP32Optimizer
 from megatron.core.process_groups_config import ProcessGroupCollection
 from megatron.core.transformer import TransformerConfig
@@ -20,8 +21,8 @@
 
 # Skip all tests in this file for LTS versions
 pytestmark = pytest.mark.skipif(
-    Version(os.getenv('NVIDIA_PYTORCH_VERSION', "24.01")) <= Version("25.05"),
-    reason="Skip layer-wise optimizer for LTS test",
+    not HAVE_EMERGING_OPTIMIZERS,
+    reason="Emerging Optimizers is not installed",
 )