Incorrect type of locale when using locally scoped useI18n composable

[DamianGlowala]

Reporting a bug?

vs

Expected behavior

Correct types for locale when using locally scoped useI18n composable

Reproduction

n/a

System Info

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- Operating System: `Windows_NT`
- Node Version:     `v16.17.0`
- Nuxt Version:     `3.0.1-rc.0-27848798.0cb9a4c`
- Nitro Version:    `2.0.0-27847631.8186a02`
- Package Manager:  `npm@8.19.3`
- Builder:          `vite`
- User Config:      `modules`, `css`, `app`, `i18n`, `googleFonts`, `fontMetrics`, `headlessui`, `image`, `build`, `typescript`, `runtimeConfig`, `security`, `nitro`
- Runtime Modules:  `@nuxtjs/tailwindcss@6.2.0`, `@nuxtjs/i18n@8.0.0-beta.7-27867903.cc6cc78`, `@nuxtjs/google-fonts@3.0.0-1`, `nuxt-headlessui@1.0.4`, `@vueuse/nuxt@9.9.0`, `@formkit/nuxt@1.0.0-beta.12`, `nuxt-icon@0.1.8`, `@nuxtjs/fontaine@0.2.4`, `@nuxt/image-edge@1.0.0-27840416.dc1ed65`
- Build Modules:    `-`
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Screenshot

No response

Additional context

No response

Validations

• Read the Contributing Guidelines
• Read the Documentation
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussions