Add banner for KubeCon NA 2025 (#7947)

Signed-off-by: Vitor Vasconcellos <[email protected]>

Author: vitorvasc

content/en/announcements/kubecon-na.md

@@ -0,0 +1,11 @@
+---
+title: KubeCon North America 2025
+date: 2025-10-01
+expiryDate: 2025-11-13
+---
+
+<i class="fas fa-bullhorn"></i> Join us in Atlanta, Georgia for [**KubeCon +
+CloudNativeCon North America 2025**][register], November 10 - 13, 2025
+
+[register]:
+  https://events.linuxfoundation.org/kubecon-cloudnativecon-north-america/register/