Remove unnecessary lines.

Author: NaotoshiFujita

.babelrc

@@ -1,20 +1,5 @@
 {
   "presets": [
-    [
-      "@babel/env",
-      {
-        "modules": false,
-        "loose": true
-      }
-    ]
-  ],
-  "env": {
-    "test": {
-      "presets": [
-        [
-          "@babel/env"
-        ]
-      ]
-    }
-  }
+    "@babel/preset-env"
+  ]
 }