[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.12.11 → v0.13.3](https://github.com/astral-sh/ruff-pre-commit/compare/v0.12.11...v0.13.3)

.pre-commit-config.yaml

@@ -16,7 +16,7 @@ ci:
 repos:
   # autoformat and lint Python code
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.12.11
+    rev: v0.13.3
     hooks:
       - id: ruff
         types_or:

docs/source/conf.py

@@ -228,6 +228,7 @@ def setup(app):
     app.add_directive("jupyterhub-generate-config", ConfigDirective)
     app.add_directive("jupyterhub-help-all", HelpAllDirective)
     app.add_directive("jupyterhub-rest-api-links", RestAPILinksDirective)
+    app.add_css_file("https://docs.jupyter.org/en/latest/_static/jupyter.css")
 
 
 # -- Read The Docs -----------------------------------------------------------
@@ -262,6 +263,7 @@ html_static_path = ["_static"]
 
 html_theme = "jupyterhub_sphinx_theme"
 html_theme_options = {
+    "announcement": "🚀 Join us in San Diego · JupyterCon 2025 · Nov 4-5 · <a href=\"https://events.linuxfoundation.org/jupytercon/program/schedule/?ajs_aid=53afb00d-be65-4a99-9112-28cdaac99463\">SCHEDULE</a> · <a href=\"https://events.linuxfoundation.org/jupytercon/register/?ajs_aid=53afb00d-be65-4a99-9112-28cdaac99463\">REGISTER NOW</a>",
     "header_links_before_dropdown": 6,
     "icon_links": [
         {