chore(ci): Opt out of Yarn 4 security for our internal packages on e2e CI tests

[slorber]

Motivation

Our Yarn Berry tests are failing on CI: https://github.com/facebook/docusaurus/actions/runs/26219679740/job/77151106100?pr=12045

Yarn recently added npmMinimalAgeGate: 1d by default:

• https://github.com/yarnpkg/berry/releases/tag/%40yarnpkg%2Fcli%2F4.15.0
• Makes npmMinimalAgeGate: 1d the default yarnpkg/berry#7135

➤ YN0000: Yarn detected that the current workflow is executed from a public pull request. For safety the hardened mode has been enabled.
➤ YN0000: It will prevent malicious lockfile manipulations, in exchange for a slower install time. You can opt-out if necessary; check our documentation for more details.

➤ YN0000: · Yarn 4.15.0
➤ YN0000: ┌ Resolution step
Resolution step
➤ YN0016: @docusaurus/core@npm:3.10.1-NEW-5590: All versions satisfying "3.10.1-NEW-5590" are quarantined

Our own packages are safe and do not need to be quarantined when downloaded from our e2e test Verdaccio repository.

Related:

• https://yarnpkg.com/configuration/yarnrc#enableHardenedMode
• https://yarnpkg.com/configuration/yarnrc#npmPreapprovedPackages

Test Plan

CI

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[github-actions]

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[slorber]

It installs now, the Yarn PnP failures are something else