- New features for `bootimage runner`

- Pass additional arguments to the run command (e.g. QEMU)

- Consider all binaries in the `target/deps` folder as test executables

- Apply `test-timeout` config key when running tests in `bootimage runner`

- Don't apply `run-args` for test executables

- Add a new `test-args` config key for test arguments

- Add a new `test-success-exit-code` config key for interpreting an exit code as success

- This is useful when the `isa-debug-exit` QEMU device is used.

- Improve printing of the run command (print string instead of array, print non-canonicalized executable path, respect `--quiet`)