Port `interesting_paths.rs` from Wasmtime's testsuite.

[sunfishcode]

Following up on ac32f57400cdcdd0425d3085c24fc7fc40011d1c, this ports another test from Wasmtime's testsuite.

[codefromthecrypt]

Is this missing a config file? When we run our runner it fails like this:

 Test interesting_paths failed
  [exit_code] 0 == 1
STDOUT:

STDERR:
usage: interesting_paths.wasm <scratch directory>

[codefromthecrypt]

yeah I think maybe it meant to have tests/rust/testsuite/interesting_paths.json with this inside?

{
    "dirs": ["fs-tests.dir"],
    "args": ["fs-tests.dir"]
}

[loganek]

Thanks for spotting that; the fix is already merged: https://github.com/WebAssembly/wasi-testsuite/pull/70

[codefromthecrypt]

Thanks I just verified it works, though I have some work to do to get it to fail the intended way on windows