revert: convert Tailwind config to TypeScript

This reverts commit 906b34d21c.

astro.config.mjs

@@ -1,5 +1,6 @@
 import { defineConfig } from "astro/config";
 import alpinejs from "@astrojs/alpinejs";
+import tailwind from "@astrojs/tailwind";
 import mdx from "@astrojs/mdx";
 
 import sitemap from "@astrojs/sitemap";
@@ -21,6 +22,11 @@ export default defineConfig({
         return item;
       }
     }),
+    tailwind({
+      config: {
+        applyBaseStyles: false
+      }
+    }),
   ],
   site: "https://www.oliverdavies.uk"
 });