Crates are published with the incorrect README

[andygrove]

Describe the bug

All datafusion crates are being published with the same top-level README, instead of the per-crate README files.

For example, see https://crates.io/crates/datafusion-optimizer. The docs here should explain what the optimizer crate is for rather than give an overview of DataFusion.

When publishing the crates, I am seeing warnings like this:

warning: readme `../../README.md` appears to be a path outside of the package, but there is already a file named `README.md` in the root of the package. The archived crate will contain the copy in the root of the package. Update the readme to point to the path relative to the root of the package to remove this warning.

To Reproduce

No response

Expected behavior

No response

Additional context

This was caused by the following commit:

8b5c1c7