`cargo package` fails to serialize TOML

[tyranron]

Problem
Cannot package or publish a crate.

cargo package errors as following:

error: failed to prepare local package for uploading

Caused by:
  values must be emitted before tables

Steps

1. git clone https://github.com/instrumentisto/medea
2. git checkout e4f1a07180fcd3ce97d754a7e2c4a671b71ae708
3. cd proto/client-api/
4. cargo package --allow-dirty --verbose

Notes

Output of cargo version:

❯ cargo version                                 
cargo 1.51.0 (43b129a20 2021-03-16)

❯ uname -a
Darwin Lilium.local 19.6.0 Darwin Kernel Version 19.6.0: Tue Jan 12 22:13:05 PST 2021; root:xnu-6153.141.16~1/RELEASE_X86_64 x86_64

It seems similar to #5906.

[ehuss]

Thanks for the report! This has been fixed in beta (1.52) and nightly (1.53) via #9300. If there is a 1.51 point release, we plan to include it there, too. For now, you can use any version except 1.51.