ci(e2e): disable fallback mode by default

[merceyz]

What's the problem this PR addresses?

Not all of the projects we cover in our e2e tests work correctly in monorepos but we don't catch this because the fallback pool allows them to access undeclared dependencies as long as they are declared in the root.

• Babel Transformer tries to load @babel/core relative to runtime parcel-bundler/parcel#4729
• Core: Fix monorepo compatibility storybookjs/storybook#11753
• fix: move babel/types from devDependencies to dependencies gatsbyjs/gatsby#26404
• fix(cli): resolve plugins relative to the package context vuejs/vue-cli#5794 (landed in v5)

How did you fix it?

Set YARN_PNP_FALLBACK_MODE=none by default in all e2e tests and opt-in where required (vue-cli)

Checklist

• I have read the Contributing Guide.
• I have set the packages that need to be released for my changes to be effective.
• I have verified that all automated PR checks pass.

[arcanis]

Given the number of failing tests, I'd tend to merge it only after the associated fixes have landed, what do you think? Otherwise we might miss other signals.

[merceyz]

Yeah, that was the plan, i'll change it to a draft to better reflect that