Add notebook 7 release

Author: SylvainCorlay

_config.yml

@@ -5,6 +5,13 @@ copyright:
 
 blog:
 
+  - url: https://blog.jupyter.org/announcing-jupyter-notebook-7-8d6d66126dcf
+    title: Announcing Jupyter Notebook 7
+    image: https://miro.medium.com/v2/resize:fit:1400/format:webp/0*1RXUtbuPrEJC95ut.jpg
+    summary: Jupyter Notebook 7 is the most significant release of the Jupyter Notebook in years. Some highlights of this release include real-time collaboration, interactive debugging, table of contents, theming and dark mode, internationalization, improved accessibility, compact view on mobile devices.
+    date: July 26th, 2023
+    authors: Jeremy Tuloup
+
   - url: https://blog.jupyter.org/jupytercon-2023-recordings-now-live-on-youtube-17564b75a2a
     title: 🎉 JupyterCon 2023 recordings now live on YouTube! 🎉
     image: https://miro.medium.com/v2/resize:fit:1400/format:webp/1*j0Cai6fnoYoJ-axQzIvpaA.png