chore(pre-commit)🔧: Update nbstripout hook version in pre-commit configuration

- Removed the older nbstripout hook version 0.6.1.
- Added the updated nbstripout hook version 0.8.1.

Author: ericmjl

.pre-commit-config.yaml

@@ -9,11 +9,6 @@ repos:
     rev: 23.10.1
     hooks:
       - id: black
-  - repo: https://github.com/kynan/nbstripout
-    rev: 0.6.1
-    hooks:
-      - id: nbstripout
-        files: ".ipynb"
   - repo: https://github.com/kynan/nbstripout
     rev: 0.8.1
     hooks: