fix(nuxt): Skip 3xx/4xx Nuxt errors in the vue:error hook

[mketiku]

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Description

#15473 stopped the client plugin from reporting Nuxt errors with a 3xx/4xx status in its app:error hook. Nuxt also calls vue:error for every error that reaches the root component, fatal or not, so a page that throws createError({ statusCode: 404 }) during setup is still reported, from the vue:error handler (mechanism auto.function.nuxt.vue-error). On client-side navigation this happens for every such 404.

This applies the same check to both hooks through a shared isIgnoredNuxtError, and adds unit tests for the client plugin's error hooks: 3xx/4xx Nuxt errors are skipped from both hooks, 5xx Nuxt errors and non-Nuxt errors are still reported. Without the fix, the vue:error 4xx test fails.

[s1gr1d]

Thanks for your contribution!
The PR title reads as "300 to 400", but the check skips 300 to 499. Suggestion: fix(nuxt): Skip 3xx/4xx Nuxt errors in the vue:error hook.

Just some small nit comments

[mketiku]

Thanks! I updated the title and addressed both nits in 1b3602c.