Reduce fixture scope from session to module (vllm-project#2187)

SUMMARY:
Fix the fixture scope to be proper level so it doesn't hold too long if
running the tests from upper level folder.

TEST PLAN:
Run all tests.

---------

Signed-off-by: Dan Huang <dahuang@redhat.com>

Author: dhuangnm

tests/llmcompressor/transformers/kv_cache/test_kv_cache.py

@@ -22,7 +22,7 @@
 ]
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture(scope="module")
 def oneshot_fixture():
     def _oneshot_fixture(tmp_path: Path):
         num_bits = 8
@@ -63,7 +63,7 @@ def _oneshot_fixture(tmp_path: Path):
     return _oneshot_fixture
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture(scope="module")
 def kv_cache_fixture():
     def _kv_cache_fixture(recipe: str, tmp_path: Path):
         num_bits = 8