[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

src/qmxgraph/__init__.py

@@ -1,7 +1,6 @@
 # This import is placed on the qmxgraph's `__init__` module to make it
 # less likely users to stumble into the "ImportError: QtWebEngineWidgets
 # must be imported before a QCoreApplication instance is created" error.
-
 # Some ugliness to successfully build the doc on ReadTheDocs...
 on_rtd = os.environ.get('READTHEDOCS') == 'True'
 if not on_rtd: