update postcss-syntax (#20)

Author: gucong3000

package.json

@@ -1,6 +1,6 @@
 {
   "name": "postcss-styled",
-  "version": "0.10.0",
+  "version": "0.24.0",
   "description": "PostCSS syntax for parsing styled components",
   "repository": {
     "type": "git",
@@ -34,15 +34,15 @@
   },
   "peerDependencies": {
     "postcss": ">=5.0.0",
-    "postcss-syntax": "^0.10.0"
+    "postcss-syntax": ">=0.24.0"
   },
   "devDependencies": {
     "chai": "^4.1.2",
     "codecov": "^3.0.2",
-    "mocha": "^5.1.1",
+    "mocha": "^5.2.0",
     "nyc": "^11.8.0",
     "postcss": "^6.0.22",
     "postcss-safe-parser": "^3.0.1",
-    "postcss-syntax": "^0.10.0"
+    "postcss-syntax": ">=0.24.0"
   }
 }