[docs] Fix pytest and add stacklevel (ray-project#26340)

doc/source/ray-contribute/getting-involved.rst

@@ -105,13 +105,15 @@ The full suite of tests is too large to run on a single machine. However, you ca
 
 .. code-block:: shell
 
- pytest -v -s python/ray/tests/test_basic.py
+ # Directly calling `pytest -v ...` may lose import paths.
+ python -m pytest -v -s python/ray/tests/test_basic.py
 
 This will run all of the tests in the file. To run a specific test, use the following:
 
 .. code-block:: shell
-
- pytest -v -s test_file.py::name_of_the_test
+ 
+ # Directly calling `pytest -v ...` may lose import paths.
+ python -m pytest -v -s test_file.py::name_of_the_test
 
 Testing for C++ development
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~

python/ray/tune/_structure_refactor.py

@@ -14,16 +14,16 @@ def warn_structure_refactor(old_module: str, new_module: str, direct: bool = Tru
 
  if direct:
  warning += (
- f"Example: Do a global search and "
+ f" Example: Do a global search and "
  f"replace `{old_module}` with `{new_module}`."
  )
 
  else:
  warning += (
- f"ATTENTION: This module may have been split or refactored. Please "
+ f"\nATTENTION: This module may have been split or refactored. Please "
  f"check the contents of `{new_module}` before making changes."
  )
 
  with warnings.catch_warnings():
  warnings.simplefilter("always")
- warnings.warn(warning, DeprecationWarning)
+ warnings.warn(warning, DeprecationWarning, stacklevel=3)