Yarn v4 lock file maintenance fails in monorepo with Yarn v1

[MikeMcC399]

How are you running Renovate?

A Mend.io-hosted app

Which platform you running Renovate on?

GitHub.com

Which version of Renovate are you using?

44.103.0

Please tell us more about your question or problem

Minimal reproduction with README on https://github.com/MikeMcC399/renovate-yarn-mixed
Failed PR on MikeMcC399/renovate-yarn-mixed#5

When a GitHub monorepo contains a mixture of Yarn v1 and Yarn v4 projects, the lock file maintenance for Yarn v4 may fail with

Artifact update problem

error This project's package.json defines "packageManager": "yarn@4.18.0". However the current global version of Yarn is 1.22.22.

It appears that Corepack is not being correctly installed / enabled. Corepack documentation advises to uninstall globally installed Yarn before installing Corepack (npm uninstall -g yarn pnpm).

Logs (if relevant)

Full log details and analysis on https://github.com/MikeMcC399/renovate-yarn-mixed#readme

Error portion example is:

Logs

branch: renovate/lock-file-maintenance

Generating yarn.lock for yarn-modern
Removing yarn-modern/yarn.lock first due to lock file maintenance upgrade
Resolved stable matching version: corepack 0.36.0
Executing command: yarn install --mode=skip-build
cwd: .../renovate-yarn-mixed/yarn-modern

error This project's package.json defines "packageManager": "yarn@4.18.0".
However the current global version of Yarn is 1.22.22.

Presence of the "packageManager" field indicates that the project is meant to
be used with Corepack.
Corepack must currently be enabled by running corepack enable in your terminal.

[MikeMcC399]

Original issue where this occurred in a production repo is cypress-io/github-action#1910

[MikeMcC399]

Is there any chance of getting a review on this issue sometime soon?

I've had to disable Yarn 4 maintenance to work around this in https://github.com/cypress-io/github-action/blob/master/renovate.json

I realize it may be an edge case to have mixed package managers in one monorepo. The reason is that these are in different example directories which show how to the use the GitHub JavaScript action https://github.com/cypress-io/github-action with some commonly used package managers (npm, pnpm, Yarn v1 Classic & Yarn v4 Modern).