rename fixtures.py to conftest.py to make codeql and flake8 happy.

Signed-off-by: Tim van Katwijk <timvankatwijk@hotmail.com>

Author: tim-vk

tests/fixtures.py tests/conftest.pytests/fixtures.py renamed to tests/conftest.py

@@ -20,13 +20,8 @@
 from dockerfile_parse.parser import image_from
 from dockerfile_parse.constants import COMMENT_INSTRUCTION
 from dockerfile_parse.util import b2u, u2b, Context, ImageName
-from tests.fixtures import dfparser, instruction
 
 NON_ASCII = "žluťoučký"
-# flake8 does not understand fixtures:
-dfparser = dfparser  # pylint: disable=self-assigning-variable
-instruction = instruction  # pylint: disable=self-assigning-variable
-
 
 @pytest.mark.parametrize(('image_string', 'dictionary'), [
     (