Add caret range for read-file-stdin

Author: simonsmith

package.json

@@ -28,7 +28,7 @@
     "postcss-custom-properties": "^5.0.0",
     "postcss-import": "^8.0.2",
     "postcss-reporter": "^1.3.0",
-    "read-file-stdin": "0.2.0",
+    "read-file-stdin": "^0.2.1",
     "stylelint": "^4.2.0"
   },
   "devDependencies": {