CVE-2021-22568

When using the dart pub publish command to publish a package to a third-party package server, the request would be authenticated with an oauth2 access_token that is valid for publishing on pub.dev. Using these obtained credentials, an attacker can impersonate the user on pub.dev. We recommend upgrading past https://github.com/dart-lang/sdk/commit/d787e78d21e12ec1ef712d229940b1172aafcdf8 or beyond version 2.15.0