Do not install yarn on toolchain

[glyh]

As title. This is to fix the below issue

darek@darek-o1labs:~/work/minaprotocol/mina$ docker run -it --entrypoint bash gcr.io/o1labs-192920/mina-toolchain@sha256:aa79d803512e2c7d7f3944a4658eec2280383df4db64be921393d93abf3782fc
opam@6c8874f324b4:~/mina$ apt-get update
Reading package lists... Done
E: List directory /var/lib/apt/lists/partial is missing. - Acquire (13: Permission denied)
opam@6c8874f324b4:~/mina$ sudo apt-get update
Get:1 http://deb.debian.org/debian bullseye InRelease [75.1 kB]
Get:2 http://deb.debian.org/debian-security bullseye-security InRelease [27.2 kB]                                                                                  
Get:3 https://deb.nodesource.com/node_24.x nodistro InRelease [12.1 kB]                   
Get:4 https://dl.yarnpkg.com/debian stable InRelease                                      
Get:5 http://deb.debian.org/debian bullseye-updates InRelease [44.0 kB]                   
Get:6 https://packages.cloud.google.com/apt cloud-sdk InRelease [1620 B]
Get:7 http://deb.debian.org/debian bullseye/main amd64 Packages [8066 kB]
Err:4 https://dl.yarnpkg.com/debian stable InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 62D54FD4003F6525
Get:8 https://deb.nodesource.com/node_24.x nodistro/main amd64 Packages [5264 B]
Get:9 https://packages.cloud.google.com/apt cloud-sdk/main all Packages [1923 kB]
Get:10 https://packages.cloud.google.com/apt cloud-sdk/main amd64 Packages [4451 kB]
Get:11 http://deb.debian.org/debian-security bullseye-security/main amd64 Packages [443 kB]
Get:12 http://deb.debian.org/debian bullseye-updates/main amd64 Packages [18.8 kB]        
Reading package lists... Done                                                                
W: GPG error: https://dl.yarnpkg.com/debian stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 62D54FD4003F6525
E: The repository 'https://dl.yarnpkg.com/debian stable InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Status: exprimenting on #18390

[glyh]

!ci-toolchain-me

[glyh]

!ci-build-me

[glyh]

!ci-nightly-me

[glyh]

^ https://buildkite.com/o-1-labs-2/mina-end-to-end-nightlies/builds/4141

[dkijania]

Nice. Approving. Then we can deal with merges conflict. Be aware that there is an issue with git state on buildkite agent which is degradating UX as you cannot just simple rerun failed merges conflict job. Unfortunately you need to rerun entire pipeline

[glyh]

!ci-toolchain-me

[glyh]

^ https://buildkite.com/o-1-labs-2/mina-toolchains-build/builds/364

[glyh]

I think it's still faster for me to open a PR against compatible and port to master later.