Extend deprecation message to description

This will make it show up on https://pre-commit.com/hooks.html

.pre-commit-hooks.yaml

diff --git a/.pre-commit-hooks.yaml b/.pre-commit-hooks.yaml
index 666a245..cef47c8 100644
--- a/.pre-commit-hooks.yaml
+++ b/.pre-commit-hooks.yaml
@@ -139,7 +139,7 @@
     types: [python]
 -   id: flake8
     name: Flake8 (deprecated, use gitlab.com/pycqa/flake8)
-    description: This hook runs flake8.
+    description: This hook runs flake8. (deprecated, use gitlab.com/pycqa/flake8)
     entry: flake8
     language: python
     types: [python]