fix(NextJS example): blog page imports

[rjvelazco]

This pull request includes changes to the examples/nextjs project to fix and improve the path handling in the blog post page and correct an import statement in the my-blog-page component.

Path handling improvements in blog post page:

• examples/nextjs/src/app/blog/post/[[...slug]]/page.js: Removed the default value for the path variable and updated the path parameter in getPageRequestParams to include the full blog post path. (examples/nextjs/src/app/blog/post/[[...slug]]/page.jsL17-R19, examples/nextjs/src/app/blog/post/[[...slug]]/page.jsL40-R43)

Import statement correction:

• examples/nextjs/src/components/my-blog-page.js: Corrected the import path for the Header component to ensure it points to the correct file.