fix: use es6 in eslint to avoid disabling linting on some lines

.eslintrc.js

@@ -1,3 +1,6 @@
 module.exports = {
-    extends: ['scratch', 'scratch/node']
+    extends: ['scratch', 'scratch/node'],
+    env: {
+        es6: true
+    }
 };

lib/batch.js

@@ -8,7 +8,7 @@
 exports.batchMap = async (arr, batchSize, func) => {
     const results = [];
     for (let i = 0; i < arr.length; i += batchSize) {
-        const result = await Promise.all( // eslint-disable-line
+        const result = await Promise.all(
             arr.slice(i, i + batchSize).map(func)
         );
         results.push(...result);