docker buildkit no longer supports --network as valid parameter

[lmtyler]

• [ x] I have tried with the latest version of Docker Desktop
• [ x] I have tried disabling enabled experimental features
• [ x] I have uploaded Diagnostics
• Diagnostics ID: 2051B26A-E0D7-4509-844F-4C4BE9D36149/20210408212242

Expected behavior

docker build --network foo . should work

Actual behavior

Error response from daemon: network mode "foo" not supported by buildkit

Information

• macOS Version: 10.15.7 (19H524)
• Docker Desktop Version: 3.2.2 (61853)

Steps to reproduce the behavior

1. docker network create foo
2. docker run --network foo -d mysql
3. docker build --network foo -t bar .

[tonistiigi]

Buildkit supports none, host, default(sandboxed) as network mode. Supporting custom network names is currently not planned as it conflicts with the portability and security guarantees.

[lmtyler]

This works in Docker Desktop V2.# on MAC and on CentOS7 currently
Has this been removed intentionally from MAC version of docker?