Respect basePath in amphtml link rel

[amiralies]

When using basePath in next config amphtml link rel doesn't respect basePath.
Note that this might be already fixed since i'm using experimental basePath in latest release (9.4.4)

[jamesmosier]

Hi @amiralies 👋 Two good first steps to help out in tracking this down:

1.) Update your project to the latest canary: npm install next@canary (or yarn add next@canary)
2.) Include a full reproduction in a repository.

[timneutkens]

I doubt this was covered yet. Should be simple to fix though

[amiralies]

I think this can be fixed in next/next-server/server/config.ts.
if amp.canonicalBase is empty and basePath is not empty then assign basePath's value to amp.canonicalBase. similar scenario is happening for assetPrefix.
correct me if i'm wrong.

[balazsorban44]

This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.