fix: exports need leading ./

Author: nlf

package.json

@@ -3,8 +3,8 @@
   "version": "1.0.0",
   "main": "lib/index.js",
   "exports": {
-    ".": "lib/index.js",
-    "./build": "lib/build/index.js"
+    ".": "./lib/index.js",
+    "./build": "./lib/build/index.js"
   },
   "types": "lib/index.d.ts",
   "files": ["lib/**/*.js", "lib/**/*.d.ts"],