Autoupdate pre-commit hooks.

.pre-commit-config.yaml

 ---
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.4.0
+    rev: v4.0.1
     hooks:
       - id: check-executables-have-shebangs
       - id: check-merge-conflict
@@ -14,19 +14,19 @@ repos:
         exclude: \.aspell\.en\.pws
 
   - repo: https://github.com/adrienverge/yamllint
-    rev: v1.26.1
+    rev: v1.26.3
     hooks:
       - id: yamllint
 
   - repo: https://github.com/amperser/proselint/
-    rev: 0.10.2
+    rev: 0.12.0
     hooks:
       - id: proselint
         types: [plain-text]
         exclude: LICENSE
 
   - repo: https://github.com/ambv/black
-    rev: 20.8b1
+    rev: 21.8b0
     hooks:
       - id: black
         exclude: &excluded_pythonscripts pythonrc.py|rabbitmqadmin
@@ -35,7 +35,7 @@ repos:
               --line-length=79
 
   - repo: https://github.com/PyCQA/prospector
-    rev: 1.3.1
+    rev: 1.5.0.1
     hooks:
       - id: prospector
         exclude: *excluded_pythonscripts
@@ -63,7 +63,7 @@ repos:
           - pyroma
 
   - repo: https://gitlab.com/pycqa/flake8.git
-    rev: 3.9.1
+    rev: 3.9.2
     hooks:
       - id: flake8
         exclude: *excluded_pythonscripts
@@ -93,7 +93,7 @@ repos:
         exclude: *excluded_shellscripts
 
   - repo: https://github.com/executablebooks/mdformat.git
-    rev: 0.7.4
+    rev: 0.7.9
     hooks:
       - id: mdformat