custom_op executor AssertionError when running different tests together

@crcrpar is already working on this.

Since Nov 3, 2025.

With `pjnl-20251103`

Repro:
```
$ pytest thunder/tests/test_recipes.py thunder/tests/test_torch_library_custom_op.py thunder/tests/test_torch_library_custom_op_with_lists.py
```

Log
```
___________________________________________________________________________________________________________________________ test_plugins_basics ____________________________________________________________________________________________________________________________

@pytest.mark.skipif(not nvfuser_available(), reason="nvFuser is not available")
def test_plugins_basics():
model = torch.nn.Sequential(torch.nn.Linear(2048, 4096), torch.nn.ReLU(), torch.nn.Linear(4096, 64))

from thunder import compile_data as get_compile_data

thunder_model = thunder.compile(model)
x = torch.randn(64, 2048)
_ = thunder_model(x)
cd = get_compile_data(thunder_model)
assert cd is not None
for ex in get_expected_executors():
> assert ex.name in [el.name for el in cd.executors_list]
E AssertionError: assert 'custom_op' in ['__ad_hoc_executor_129167309031136', '__ad_hoc_executor_129167309030176', 'nvfuser', 'torch', 'python']
E + where 'custom_op' = thunder.extend.OperatorExecutor('custom_op').name

thunder/tests/test_recipes.py:200: AssertionError
_________________________________________________________________________________________________________________________ test_plugins_composition _________________________________________________________________________________________________________________________

monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x757a1bb59100>

@pytest.mark.skipif(not nvfuser_available(), reason="nvFuser is not available")
@pytest.mark.skipif(IS_WINDOWS, reason="libuv error with PT build on windows")
def test_plugins_composition(monkeypatch):
model = torch.nn.Sequential(torch.nn.Linear(2048, 4096), torch.nn.ReLU(), torch.nn.Linear(4096, 64))

monkeypatch.setenv("LOCAL_RANK", "0")

with patch("thunder.jit") as mock_jit:
_ = thunder.compile(model, plugins="fp8")
call_args = mock_jit.call_args
assert "transformer_engine_v1" in [el.name for el in call_args.kwargs["executors"]]
for ex in get_expected_executors():
> assert ex.name in [el.name for el in call_args.kwargs["executors"]]
E AssertionError: assert 'custom_op' in ['__ad_hoc_executor_129167308652272', 'transformer_engine_v1', 'nvfuser']
E + where 'custom_op' = thunder.extend.OperatorExecutor('custom_op').name

thunder/tests/test_recipes.py:216: AssertionError
========================================================================================================================= short test summary info ==========================================================================================================================
FAILED thunder/tests/test_recipes.py::test_plugins_basics - AssertionError: assert 'custom_op' in ['__ad_hoc_executor_129167309031136', '__ad_hoc_executor_129167309030176', 'nvfuser', 'torch', 'python']
FAILED thunder/tests/test_recipes.py::test_plugins_composition - AssertionError: assert 'custom_op' in ['__ad_hoc_executor_129167308652272', 'transformer_engine_v1', 'nvfuser']
=============================================================================================================== 2 failed, 17 passed, 113 warnings in 46.96s ================================================================================================================
```

NOTE: The test runs fine when run independently - `pytest thunder/tests/test_recipes.py`

cc: @crcrpar