Panic due to paths override in .cargo/config

[zmwangx]

cargo 1.46.0 (149022b1d 2020-07-17)
cargo-outdated v0.9.11

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I use a paths override in .cargo/config

paths = ["../another-crate"]

when working on two related crates that reside in different repos. cargo-outdated doesn't like that at all and merely panics:

$ RUST_BACKTRACE=1 cargo outdated -R
thread 'main' panicked at 'no entry found for key', /Users/zmwang/.cargo/registry/src/github.com-1ecc6299db9ec823/cargo-outdated-0.9.11/src/cargo_ops/temp_project.rs:654:20
stack backtrace:
   0: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
   1: core::fmt::write
   2: std::io::Write::write_fmt
   3: std::panicking::default_hook::{{closure}}
   4: std::panicking::rust_panic_with_hook
   5: rust_begin_unwind
   6: core::panicking::panic_fmt
   7: core::option::expect_failed
   8: cargo_outdated::cargo_ops::temp_project::manifest_paths::manifest_paths_recursive
   9: cargo_outdated::cargo_ops::temp_project::manifest_paths::manifest_paths_recursive
  10: cargo_outdated::cargo_ops::temp_project::TempProject::from_workspace
  11: cargo_outdated::execute
  12: cargo_outdated::main
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

Apparently related to #188, merged with a quite prophetic comment

Let's see how that works. Hopefully people won't be using things like index path override that uses a relative path.

Well, people do use things like that...

Personally I don't care about respecting the paths override, a helpful error message saying something along the lines of "you're doing something unsupported in .cargo/config" should be fine. Just don't want to spend twenty minutes trying to make sense of why it's panicking.