Docs preview: udate to ubuntu latest

Author: keenanjohnson

.github/workflows/docs-preview.yml

@@ -13,7 +13,7 @@ concurrency: preview-${{ github.ref }}
 
 jobs:
   deploy-preview:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v3