Ensured branch slug is generated before building project on preview env deployment

scripts/set-homepage.js

@@ -0,0 +1,13 @@
+const argv = process.argv.slice(2);
+const [ homepage ] = argv;
+
+if (!homepage) {
+  throw new Error('Homepage has to be provided as the first arg for this script');
+}
+
+const packageJsonPath = `${__dirname}/../package.json`;
+const packageJson = require(packageJsonPath);
+const fs = require('fs');
+
+packageJson.homepage = homepage;
+fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2));