test: ensure empty build before empty test

Author: SebastianSpeitel

package.json

@@ -6,8 +6,8 @@
   "ascMain": "assembly/index.ts",
   "types": "assembly/index.ts",
   "scripts": {
-    "pretest": "npm run asbuild:empty",
     "test": "asp --verbose --nologo && npm run test:empty",
+    "pretest:empty": "npm run asbuild:empty",
     "test:empty": "diff build/empty.wat assembly/__tests__/empty.wat",
     "test:ci": "asp --summary && npm run test:empty",
     "asbuild:untouched": "asc assembly/index.ts --target debug",