fix(templates): tailwind file extension is wrong in website template components.json file (#9342)

**symptoms:** 
when using website template default, if you then want to add more shadcn
components on frontend it errors out because tailwind config extension
is wrong in components.json:

**example:**

>npx shadcn@latest add alert
✔ Checking registry.
⠋ Updating tailwind.config.js
Something went wrong. Please check the error below for more details. If
the problem persists, please open an issue on GitHub.

ENOENT: no such file or directory, open
'*MYPROJECTPATHREMOVED*\tailwind.config.js'

**FIX:**

Can be fixed simply by updating reference in components.json to
tailwind.config.mjs

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Co-authored-by: Paul Popus <paul@payloadcms.com>

Author: marketsystems

templates/website/components.json

@@ -4,7 +4,7 @@
   "rsc": true,
   "tsx": true,
   "tailwind": {
-    "config": "tailwind.config.js",
+    "config": "tailwind.config.mjs",
     "css": "src/app/(frontend)/globals.css",
     "baseColor": "slate",
     "cssVariables": true,