Replace lodash 'defaults' usage with ES6 Spread initializer (#11797)

Co-authored-by: Corey Farrell <git@cfware.com>

packages/babel-cli/src/babel/dir.js

@@ -1,6 +1,5 @@
 // @flow
 
-import defaults from "lodash/defaults";
 import debounce from "lodash/debounce";
 import { sync as makeDirSync } from "make-dir";
 import slash from "slash";
@@ -48,15 +47,10 @@ export default async function ({
     const dest = getDest(relative, base);
 
     try {
-      const res = await util.compile(
-        src,
-        defaults(
-          {
-            sourceFileName: slash(path.relative(dest + "/..", src)),
-          },
-          babelOptions,
-        ),
-      );
+      const res = await util.compile(src, {
+        ...babelOptions,
+        sourceFileName: slash(path.relative(dest + "/..", src)),
+      });
 
       if (!res) return FILE_TYPE.IGNORED;
 

packages/babel-cli/src/babel/file.js

@@ -1,7 +1,6 @@
 // @flow
 
 import convertSourceMap from "convert-source-map";
-import defaults from "lodash/defaults";
 import sourceMap from "source-map";
 import slash from "slash";
 import { sync as makeDirSync } from "make-dir";
@@ -127,16 +126,10 @@ export default async function ({
   async function stdin(): Promise<void> {
     const code = await readStdin();
 
-    const res = await util.transform(
-      cliOptions.filename,
-      code,
-      defaults(
-        {
-          sourceFileName: "stdin",
-        },
-        babelOptions,
-      ),
-    );
+    const res = await util.transform(cliOptions.filename, code, {
+      ...babelOptions,
+      sourceFileName: "stdin",
+    });
 
     output([res]);
   }
@@ -177,22 +170,17 @@ export default async function ({
         sourceFilename = slash(sourceFilename);
 
         try {
-          return await util.compile(
-            filename,
-            defaults(
-              {
-                sourceFileName: sourceFilename,
-                // Since we're compiling everything to be merged together,
-                // "inline" applies to the final output file, but not to the individual
-                // files being concatenated.
-                sourceMaps:
-                  babelOptions.sourceMaps === "inline"
-                    ? true
-                    : babelOptions.sourceMaps,
-              },
-              babelOptions,
-            ),
-          );
+          return await util.compile(filename, {
+            ...babelOptions,
+            sourceFileName: sourceFilename,
+            // Since we're compiling everything to be merged together,
+            // "inline" applies to the final output file, but not to the individual
+            // files being concatenated.
+            sourceMaps:
+              babelOptions.sourceMaps === "inline"
+                ? true
+                : babelOptions.sourceMaps,
+          });
         } catch (err) {
           if (!cliOptions.watch) {
             throw err;