[pre-commit.ci] pre-commit autoupdate (#186)

* [pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/psf/black: 21.10b0 → 21.12b0](psf/black@21.10b0...21.12b0)

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

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

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.pre-commit-config.yaml

@@ -12,7 +12,7 @@ repos:
         additional_dependencies: [toml]
         exclude: docs/pages
   - repo: https://github.com/psf/black
-    rev: "21.10b0"
+    rev: "21.12b0"
     hooks:
       - id: black
   - repo: https://github.com/kynan/nbstripout

src/corner/arviz_corner.py

@@ -23,7 +23,6 @@ def _get_labels(plotters, labeller=None):
             for var_name, selection, _ in plotters
         ]
 
-
 except ImportError:
     from arviz.labels import BaseLabeller
     from arviz.sel_utils import xarray_to_ndarray, xarray_var_iter