Read omnivore API key from env

src/_data/links.js

@@ -1,5 +1,5 @@
 const fs = require('node:fs');
-const apiKey = 'bf7b63c4-b6f2-4568-b554-4a3440460070';
+const apiKey = process.env.OMNIVORE_API_KEY;
 const cacheFile = '.cache/links.json';
 
 const query = `query Search($after: String, $first: Int, $query: String, $format: String, $includeContent: Boolean) {