[deps]: Update withastro/action action to v6

Author: renovate[bot]

.github/workflows/deploy.yml

@@ -21,7 +21,7 @@ jobs:
           persist-credentials: false
 
       - name: Install, build, and upload your site output
-        uses: withastro/action@44cbafd43567733e3b007918c6e0711480560516 # v3.0.0
+        uses: withastro/action@74d664f13f9f9063e37b49d74a74613dbf94db3c # v6.0.0
 
   deploy:
     name: Deploy