Fix commonjs & umd exports (#5030)

lib/axios.js

@@ -75,12 +75,10 @@ axios.formToJSON = thing => {
   return formDataToJSON(utils.isHTMLForm(thing) ? new FormData(thing) : thing);
 };
 
-export default axios;
-
 export {
+  axios as default,
   Axios,
   AxiosHeaders,
   AxiosError,
   CanceledError,
 };
-

rollup.config.js

@@ -56,7 +56,7 @@ export default async () => {
         file: `dist/${outputFileName}`,
         name,
         format: "umd",
-        exports: "default",
+        exports: "named",
         banner
       }
     }),
@@ -77,7 +77,7 @@ export default async () => {
         file: `dist/node/${name}.cjs`,
         format: "cjs",
         preferConst: true,
-        exports: "default",
+        exports: "named",
         banner
       },
       plugins: [