Documentation links point to 2.12 and not 2.13

[richard-cox]

Setup

• Rancher version: v2.13.0 (dev of)

Describe the bug

• links to documentation point to the incorrect version

To Reproduce

• Home Page --> Links card --> click on Docs link

Result

• Docs link goes to https://ranchermanager.docs.rancher.com/v2.12

Expected Result

• Docs link goes to https://ranchermanager.docs.rancher.com/v2.13