fix: copy migration.json (#6)

Author: timdeschryver

package.json

@@ -7,7 +7,7 @@
     "prebuild": "rimraf dist",
     "build": "npm run build:library && npm run build:migrations && npm run build:readme",
     "build:library": "ng build --prod testing-library",
-    "build:migrations": "tsc -p ./projects/testing-library/migrations/tsconfig.migrations.json",
+    "build:migrations": "tsc -p ./projects/testing-library/migrations/tsconfig.migrations.json && cp ./projects/testing-library/migrations/migration.json ./dist/@angular-extensions/testing-library/migrations",
     "build:readme": "cp ./README.md ./dist/@angular-extensions/testing-library",
     "test": "jest --config ./projects/jest.lib.config.js",
     "test:app": "jest --config ./src/jest.app.config.js",