Copy Redpanda runtime assets during build (#1357)

Author: cristianrgreco

packages/modules/redpanda/package.json

@@ -25,8 +25,9 @@
     "access": "public"
   },
   "scripts": {
-    "prepack": "shx cp ../../../README.md . && shx cp ../../../LICENSE . && shx cp -r src/assets build",
-    "build": "tsc --project tsconfig.build.json"
+    "prepack": "shx cp ../../../README.md . && shx cp ../../../LICENSE .",
+    "build": "tsc --project tsconfig.build.json",
+    "postbuild": "shx cp -r src/assets build"
   },
   "dependencies": {
     "handlebars": "^4.7.9",