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

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

Author: pre-commit-ci[bot]

README.md

@@ -36,6 +36,7 @@ pip install carbonplan[styles]
 
 ```python
 from carbonplan.styles.mpl import set_theme
+
 # this is the same things as
 from carbonplan_styles.mpl import set_theme
 ```