Update pre-commit deps

Author: benjeffery

.pre-commit-config.yaml

@@ -1,26 +1,26 @@
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.2.0
+    rev: v3.4.0
     hooks:
       - id: check-merge-conflict
       - id: debug-statements
       - id: mixed-line-ending
       - id: check-case-conflict
       - id: check-yaml
   - repo: https://github.com/benjeffery/pre-commit-clang-format
-    rev: master
+    rev: c21a74d089aaeb86c2c19df371c7e7bf40c07207
     hooks:
     - id: clang-format
       exclude: dev-tools|examples
       verbose: true
   - repo: https://github.com/asottile/reorder_python_imports
-    rev: v2.3.5
+    rev: v2.3.6
     hooks:
       - id: reorder-python-imports
         args: [--application-directories=python,
                --unclassifiable-application-module=_tskit]
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.7.2
+    rev: v2.7.4
     hooks:
       - id: pyupgrade
         args: [--py3-plus, --py36-plus]
@@ -33,13 +33,13 @@ repos:
         # loop that throws an error before black excludes it
         args: [python/tskit, python/setup.py, python/stress_lowlevel.py]
   - repo: https://gitlab.com/pycqa/flake8
-    rev: 3.8.3
+    rev: 3.8.4
     hooks:
       - id: flake8
         args: [--config=python/.flake8]
         additional_dependencies: ["flake8-bugbear==20.1.4", "flake8-builtins==1.5.2"]
   - repo: https://github.com/asottile/blacken-docs
-    rev: v1.8.0
+    rev: v1.9.1
     hooks:
       - id: blacken-docs
         args: [--skip-errors]