[code-infra] Ensure translations.json is present in all @mui/docs package builds (#45626)

Co-authored-by: MUI bot <[email protected]>

Author: LukasTy

packages/mui-docs/package.json

@@ -28,7 +28,7 @@
     "build:node": "node ../../scripts/build.mjs node",
     "build:stable": "node ../../scripts/build.mjs stable",
     "build:types": "tsx ../../scripts/buildTypes.mts",
-    "build:copy-files": "node ../../scripts/copyFiles.mjs ./src/translations/translations.json:./translations/translations.json ./src/translations/translations.json:./node/translations/translations.json",
+    "build:copy-files": "node ../../scripts/copyFiles.mjs ./src/translations/translations.json:./translations/translations.json ./src/translations/translations.json:./esm/translations/translations.json ./src/translations/translations.json:./modern/translations/translations.json",
     "prebuild": "rimraf build",
     "release": "pnpm build && pnpm publish",
     "test": "exit 0",