[Refactor] Simplify isVSCode implementation

[gonzaloriestra]

What has changed?

Refactored isVSCode in packages/cli-kit/src/public/node/vscode.ts to pass .vscode directly as target to findPathUp using {cwd: root} option and returning Boolean(config) directly.

How to test your changes?

CI

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PR created automatically by Jules for task 2799281686358303100 started by @gonzaloriestra

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