Added page to UI about database resize (#6893)

* upscale-database-add: added new folder with topic and screenshot

* upscale-database-add: changed labels from upscale to resize

* upscale-database-add: updates after dev changes

* upscale-database-add: added published date

---------

Co-authored-by: Magda Sulik <you@example.com>

docs/products/databases/managed-databases/guides/upscale-database/index.md

@@ -0,0 +1,29 @@
+---
+title: "Resize A Database Cluster"
+description: "Learn how to resize your database cluster."
+authors: ["Linode"]
+published: 2024-04-09
+---
+
+{{< content "dbass-eos" >}}
+
+You can upscale database clusters to adapt them to your needs. Clusters can’t be downscaled.
+
+{{< note type="alert" >}}
+This operation causes downtime for the resized node clusters.
+
+{{< /note >}}
+
+1. Log in to the [Cloud Manager](https://cloud.linode.com/) and select **Databases** from the left navigation menu.
+
+1. Select a database cluster from the list. 
+
+1. Navigate to the **Resize** tab.
+
+1. In the *Choose a plan* section, select a new plan for your database cluster. 
+
+    ![Screenshot of Choose a plan section](upscale-plan.png)
+
+1. In the *Summary* section, verify the changes. Click **Resize Database Cluster**.
+
+1. Follow the on-screen instructions and click **Resize Cluster** to confirm. The cluster will be upscaled within two hours.