[Packaging] rust2rpm: ERROR: No license files were detected

Start by inspecting Cargo.toml and Cargo.toml.orig, then compare the files included in the crates.io download with the repository's release process. Verify how rust2rpm detects license files and ensure the next crate archive contains the project's license file; confirm by rerunning rust2rpm pkgx without -I.

I wanted to package pkgx in Copr (so it can be installed using dnf on rpm-based distros, such as Fedora and RHEL).

I ran into the following error with rust2rpm:

$ rust2rpm pkgx
ERROR: No license files were detected. In almost all cases, this is an issue with
       the upstream project that should be reported.
• To temporarily ignore this issue, use the '--ignore-missing-license-files' / '-I'
  flag - for example, when manually including license files from the upstream
  project, or for test builds.

I think the solution is to include the license file in https://crates.io/api/v1/crates/pkgx/2.7.0/download (or the next release). I don't know how to do that. But what I know is that, currently, the files are:

$ tar xfv download.tar 
pkgx-2.7.0/.cargo_vcs_info.json
pkgx-2.7.0/Cargo.lock
pkgx-2.7.0/Cargo.toml
pkgx-2.7.0/Cargo.toml.orig
pkgx-2.7.0/README.md
pkgx-2.7.0/src/args.rs
pkgx-2.7.0/src/dump.rs
pkgx-2.7.0/src/execve.rs
pkgx-2.7.0/src/help.rs
pkgx-2.7.0/src/main.rs
pkgx-2.7.0/src/query.rs
pkgx-2.7.0/src/resolve.rs
pkgx-2.7.0/src/spinner.rs
pkgx-2.7.0/src/tests/main.rs
pkgx-2.7.0/src/tests/mod.rs
pkgx-2.7.0/src/which.rs
pkgx-2.7.0/src/x.rs

For now, I'll use the -I flag.