fix(snapshot): fail test when snapshot assertion is used with test.fails

[hi-ogawa]

Description

• Closes Dont update snapshot inside it.fails #9495

expect.soft handling is a bit annoying 🤔 I ended up with using error.__vitest_test_syntax_error__ to allow communicate between expect/runner/vitest packages basically.

This is likely a breaking change since users can do really weird thing with snapshot.

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[sheremet-va]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

[hi-ogawa]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

I removed one test from test/core/test/snapshot.test.ts and that's the one.