fix: Add missing d.ts file in ecs-morgan-format (#170)

Author: imsuvesh

packages/ecs-morgan-format/package.json

@@ -5,7 +5,8 @@
   "main": "index.js",
   "types": "index.d.ts",
   "files": [
-    "index.js"
+    "index.js",
+    "index.d.ts"
   ],
   "repository": {
     "type": "git",