Failure when workspace uses the `default-members` field.

[stormshield-gt]

The action failed when a workspace with a root package use the default-members field.

In seems that's because a package is passed twice to cargo publish. I get the following log:

Found packages: vaultrs-login, vaultrs
Checking packages consistency
Sorting packages according to dependencies
Publishing package 'vaultrs'
/home/runner/.cargo/bin/cargo publish
error: the `-p` argument must be specified to select a single package to publish
Error: Error: The process '/home/runner/.cargo/bin/cargo' failed with exit code 101

For our packages, moving from default-members was a workaround, see this commit.