chore: make Yarn v1 version installation explicit

[MikeMcC399]

Situation

In scripts/update-cypress-latest-yarn.sh Yarn v1 Classic is globally installed with npm install yarn@latest -g

yarn@latest currently equates to yarn@1.22.22

The Yarn v1 module owner announced plans to re-use the npm yarn module for future Switch usage with Yarn v6.

Change

Replace yarn@latest with yarn@1 to install the latest Yarn v1 Classic version in the scripts/update-cypress-latest-yarn.sh script.

Verify

Execute

./scripts/update-cypress-latest-yarn.sh

and confirm no errors.

---

Note

Low Risk
Only affects a maintenance script’s global Yarn version specifier; no runtime or CI product logic changes.

Overview
Pins global Yarn Classic installs in scripts/update-cypress-latest-yarn.sh by changing npm install yarn@latest -g to npm install yarn@1 -g in both places (start of the Yarn 1 Classic section and after disabling corepack post–Yarn 4 Modern).

Behavior stays “latest Yarn 1.x,” but the tag avoids accidentally pulling a future non–v1 release if the yarn npm package is republished for Yarn v6.

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[cypress-app-bot]

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