Use alert-md shortcode

Author: chalin

content/en/blog/2025/kubecon-eu.md

@@ -113,15 +113,15 @@ cloud native observability projects. This event will be held on Tuesday, April
 1, 2025, from 9:00 - 17:25. There will be several sessions on OpenTelemetry as
 well.
 
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 You need an _all-access_ pass to attend **Observability Day**. For details, see
 [KubeCon registration][registration].
 
 [registration]:
   https://events.linuxfoundation.org/kubecon-cloudnativecon-europe/register/?utm_source=opentelemetry&utm_medium=all&utm_campaign=KubeCon-EU-2025&utm_content=blog
 
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 - **[Sponsored Keynote: The Future of Observability: Trends, AI, and New Relic’s Vision for a Smarter Stack](https://sched.co/1u5jm)**<br>
   by Harry Kimpel, New Relic<br> Tuesday, April 1 • 10:00 - 10:05