[release] remove .dart_tool directory from uploaded zip (#58135)

Fixes #58003

The .dart_tool directory can contain build assets, as well as the package_config.json file - the replacement for .packages. Remove it for the same reason we remove .packages
https://dart.googlesource.com/external/github.com/flutter/flutter/+/52db5e29f1d11989af03353d505507d54ddc1c23
1 file changed
tree: 6a8edda9f529ee570f627dfe0412763b593d1c28
  1. commits.json