Add ruff, remove black, isort, flake8, pylint (#3092)

* black, isort, flake8 -> ruff

* remove unused

* add back needed import

* fix

tests/e2e/solo/test_flex.py

@@ -22,7 +22,6 @@ class TestPackedFlex(unittest.TestCase):
     @require_torch_2_6_0
     @with_temp_dir
     def test_loss_llama(self, temp_dir):
-        # pylint: disable=duplicate-code
         cfg = DictDefault(
             {
                 "base_model": "HuggingFaceTB/SmolLM2-135M",

tests/e2e/solo/test_relora_llama.py

@@ -20,7 +20,6 @@ class TestReLoraLlama(unittest.TestCase):
 
     @with_temp_dir
     def test_relora(self, temp_dir):
-        # pylint: disable=duplicate-code
         cfg = DictDefault(
             {
                 "base_model": "HuggingFaceTB/SmolLM2-135M",
@@ -76,9 +75,9 @@ class TestReLoraLlama(unittest.TestCase):
 
         train(cfg=cfg, dataset_meta=dataset_meta)
         check_model_output_exists(Path(temp_dir) / "checkpoint-100/adapter", cfg)
-        assert (
-            Path(temp_dir) / "checkpoint-100/relora/model.safetensors"
-        ).exists(), "Relora model checkpoint not found"
+        assert (Path(temp_dir) / "checkpoint-100/relora/model.safetensors").exists(), (
+            "Relora model checkpoint not found"
+        )
 
         check_tensorboard(
             temp_dir + "/runs", "train/grad_norm", 0.2, "grad_norm is too high"