Set correct versions for black and reuse

Author: evaherrada

.pre-commit-config.yaml

@@ -4,11 +4,11 @@
 
 repos:
 -   repo: https://github.com/python/black
-    rev: latest
+    rev: 20.8b1
     hooks:
     - id: black
 -   repo: https://github.com/fsfe/reuse-tool
-    rev: latest
+    rev: v0.12.1
     hooks:
     - id: reuse
 -   repo: https://github.com/pre-commit/pre-commit-hooks