Merge pull request #468 from plotly/sept2026-webinar-ad

Change sidebar ad to sept 2026 webinar

Author: red-patience

_includes/layouts/webinar_plug.html

@@ -1,5 +1,5 @@
 
-   <a href="https://plotly.com/webinars/plotly-studio-embedded/?source=graphing_libraries&medium=documentation&campaign=plotly-studio-embedded-27aug2026&content=sidebar" target="_blank">
-     <img src="https://images.prismic.io/plotly-marketing-website-2/OrBL5FG-AQWYQ8n6_introducing-plotly-studio-embedded-docs.jpg?auto=format,compress"
-     style="width: 200px; height: 200px; position: fixed; bottom: 10px; left: 50px" alt="Sign up for the upcoming webinar: Introducing Plotly Studio Embedded">
+   <a href="https://plotly.com/webinars/plotly-studio-projects/?source=graphing_libraries&medium=documentation&campaign=plotly-studio-projects-16sept2026&content=sidebar" target="_blank">
+     <img src="https://images.prismic.io/plotly-marketing-website-2/oXGLlCJWomRqcLDk_plotly-studio-projects.jpg?auto=format,compress"
+     style="width: 200px; height: 200px; position: fixed; bottom: 10px; left: 50px" alt="Sign up for the upcoming webinar: One Workspace for Every Session with Plotly Studio Projects">
    </a>