npm: don't pack *.spec.d.ts files

Author: gustavohenke

package.json

@@ -69,7 +69,8 @@
     "index.js",
     "index.mjs",
     "!**/fixtures",
-    "!**/*.spec.js"
+    "!**/*.spec.js",
+    "!**/*.spec.d.ts"
   ],
   "jest": {
     "preset": "ts-jest",