chore: change config file extension

Author: kopy-kat

next.config.js

@@ -1,6 +1,6 @@
 const withNextra = require("nextra")({
   theme: "nextra-theme-docs",
-  themeConfig: "./theme.config.tsx",
+  themeConfig: "./theme.config.js",
 });
 
 module.exports = {

package.json

@@ -23,7 +23,8 @@
     "nextra-theme-docs": "latest",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
-    "react-icons": "^4.12.0"
+    "react-icons": "^4.12.0",
+    "sharp": "^0.33.4"
   },
   "devDependencies": {
     "@types/node": "18.11.10",