Adds the specific path that caused a failure

[scottopell]

What does this PR do?

Adds the path that caused an expect to fail.

Motivation

After:

thread 'tokio-runtime-worker' panicked at lading/src/common.rs:60:17:
Full directory path does not exist: /captures/target.stdout.log
stack backtrace:
   0: rust_begin_unwind

(before the path was not present)

Related issues

A list of issues either fixed, containing architectural discussions, otherwise relevant
for this Pull Request.

Additional Notes

Anything else we should know when reviewing?