Incomplete pyproject.toml support

[netsandbox]

While 53bc302 added isort with pyproject.toml support as a dependency,
it was missed to update the _search_config_on_path method to also
look for a tool.isort section in pyproject.toml:

flake8-isort/flake8_isort.py

Lines 128 to 151 in 27eb1c1

	def _search_config_on_path(self, path):
	# type: (str) -> Optional[str] # noqa: F821
	"""Search for isort configuration files at the specifed path.
	Args:
	path: The path to search for config files on.
	Return:
	str: the isort config if found otherwise, None
	"""
	for config_file in ('.isort.cfg', '.editorconfig'):
	config_file_path = os.path.join(path, config_file)
	if os.path.isfile(config_file_path):
	return config_file_path
	# Check for '[isort]' section in other configuration files.
	for config_file in ('tox.ini', 'setup.cfg', '.flake8'):
	config_file_path = os.path.join(path, config_file)
	config = SafeConfigParser()
	config.read(config_file_path)
	if 'isort' in config.sections():
	return config_file_path
	return None

If you currently have tool.isort section in pyproject.toml, you always get the following error:
I002 no configuration found (.isort.cfg or [isort] in configs)

[jnns]

Thanks for mentioning this. There's already a pull request to improve support for pyproject.toml and that will resolve this issue.

[caiolopes]

Can we close this since #79 is merged?

[gforcada]

@caiolopes yes, thanks for taking the time to review what can be closed already 💯