_content/solutions: update link to the Dropbox blog

The old https://blogs.dropbox.com is inaccessible.

Change-Id: I48de0ea61be4ea7954d461a1bea4e6d3b6cfd785
Reviewed-on: https://go-review.googlesource.com/c/website/+/602836
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

_content/solutions/cloud.md

@@ -89,7 +89,7 @@ The major Cloud providers ([GCP](https://cloud.google.com/go/home), [AWS](https:
     desc: Dropbox was built on Python, but in 2013 decided to migrate their performance-critical backends to Go. Today, most of the company’s infrastructure is written in Go.
     ctas:
       - text: Dropbox libraries
-        url: https://blogs.dropbox.com/tech/2014/07/open-sourcing-our-go-libraries/
+        url: https://dropbox.tech/infrastructure/open-sourcing-our-go-libraries
   - company: Mercado Libre
     url: https://www.mercadolibre.com.ar/
     logoSrc: mercadolibre_light.svg