pre-commit updates in the template (sunpy#127)

This is an autogenerated PR, which updates the `{{
cookiecutter.package_name }}/.pre-commit-config.yaml` file.

Author: Cadair

{{ cookiecutter.package_name }}/.pre-commit-config.yaml

@@ -1,7 +1,7 @@
 repos:
     # This should be before any formatting hooks like isort
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: "v0.6.7"
+    rev: "v0.6.8"
     hooks:
       - id: ruff
         args: ["--fix"]