fixes the following error when trying to run nix run .#cargo-nix from a shell that doesn't have rustc available
Error: while retrieving metadata about ./Cargo.toml: `cargo metadata` exited with an error: warning: resolver for the non root package will be ignored, specify resolver at the workspace root:
package: /Users/nasso/src/tangled.org-core/crates/gix-chunk/Cargo.toml
workspace: /Users/nasso/src/tangled.org-core/Cargo.toml
warning: resolver for the non root package will be ignored, specify resolver at the workspace root:
package: /Users/nasso/src/tangled.org-core/crates/gix-commitgraph/Cargo.toml
workspace: /Users/nasso/src/tangled.org-core/Cargo.toml
error: could not execute process `rustc -vV` (never executed)
Caused by:
No such file or directory (os error 2)