fix(microfrontends): respect packageName field (#10383)
### Description
This PR does 2 things:
- Adds a warning if a package is referenced in `microfrontends.json`
that is not present in the monorepo
- Uses `packageName` over the `applications` key if present
### Testing Instructions
Added unit tests.
Verified warnings now are present if you reference a package that isn't
found in the monorepo:
```
[0 olszewski@macbookpro] /Users/olszewski/code/vercel/microfrontends $ turbo_dev --skip-infer dev -F nextjs-app-marketing -F nextjs-app-docs --dry=json > /dev/null
turbo 2.5.1
WARNING Unable to find packages referenced in 'microfrontends.json' in workspace.Local proxy will not route to the following applications if they are running locally: nextjs-app-marketing-test
```
Verified that proxy is now started if every application uses a
`packageName` that differs from the key in `applications`.
---------
Co-authored-by: Thomas Knickman <tom.knickman@vercel.com>
