test: Migrate to Vitest

[timfish]

This PR:

• Migrates all tests to Vitest
• I had to change the CI cache keys because changing a package.json resulted in no lock change and a build failure
• Test usages of the Vite plugin had to add as unknown as vite.Plugin because the Vite versions varied between the plugin and integration tests. This does not impact end users because it will use their Vite version.

[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

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New Features ✨

• Use crypto.randomUUID rather than uuid by timfish in #892

Other

• test: Migrate to Vitest by timfish in #894

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[timfish]

Ah, just found that the e2e tests are disabled completely!

sentry-javascript-bundler-plugins/.github/workflows/checks.yml

Lines 168 to 171 in 644e5e2

	if:
	(github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository) &&
	github.actor != 'dependabot[bot]' &&
	false # Debug ID backend changes broke the E2E tests, we need to revisit them