Handle missing .cache directory

src/_data/links.js

@@ -52,6 +52,9 @@ const cachedContent = () => {
 }
 
 const storeCache = (content = []) => {
+    if (!fs.existsSync('.cache')) {
+        fs.mkdirSync('.cache');
+    }
     fs.writeFileSync(cacheFile, JSON.stringify(content));
 }