feat: allow reading cjs config file

Author: slavik-chapelskyi

src/setup.ts

@@ -4,7 +4,7 @@ import {start} from '@shelf/elasticsearch-local';
 const cwd = require('cwd');
 
 module.exports = function startES() {
-  const path = process.env.JEST_ELASTICSEARCH_CONFIG || resolve(cwd(), 'jest-es-config.js');
+  const path = process.env.JEST_ELASTICSEARCH_CONFIG || resolve(cwd(), 'jest-es-config');
   const config = require(path)();
 
   return start(config);