Debian uses a separate registry for the packages it distributes. Checksums for some Debian packages don't match anything that's available on crates.io, which is the default source of dependencies. *linked-hash-map* in particular doesn't provide any hash.
As a result, Debian's `Cargo.lock` and crates.io's `Cargo.lock` are not matching, and building is only possible with one or the other, depending on what's checked in.
As a separate issue, Debian packages are usually not checked in in multiple versions, so checking in Debian's `Cargo.lock` would result in the package not building whenever a bugfix is distributed (due to checksum changes).
This change removes the crates.io `Cargo.lock` so that a new one will be created whenever a .deb is built, solving the above. What keeps falsely passing builds from happening is `Cargo.toml` specifying no interface changes, as well as Build-Depends, which seem enough for any other Debian package.
