[functional-tests] Move thin_check functional tests to Rust.

They'll be run as part of 'cargo test' now.

Cargo.lock

@@ -107,6 +107,18 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "duct"
+version = "0.13.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f90a9c3a25aafbd538c7d40a53f83c4487ee8216c12d1c8ef2c01eb2f6ea1553"
+dependencies = [
+ "libc",
+ "once_cell",
+ "os_pipe",
+ "shared_child",
+]
+
 [[package]]
 name = "env_logger"
 version = "0.7.1"
@@ -260,6 +272,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "json"
+version = "0.12.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "078e285eafdfb6c4b434e0d31e8cfcb5115b651496faca5749b88fafd4f23bfd"
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -369,6 +387,16 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b631f7e854af39a1739f401cf34a8a013dfe09eac4fa4dba91e9768bd28168d"
 
+[[package]]
+name = "os_pipe"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fb233f06c2307e1f5ce2ecad9f8121cffbbee2c95428f44ea85222e460d0d213"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "pin-project"
 version = "0.4.23"
@@ -543,6 +571,16 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71d301d4193d031abdd79ff7e3dd721168a9572ef3fe51a1517aba235bd8f86e"
 
+[[package]]
+name = "shared_child"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8cebcf3a403e4deafaf34dc882c4a1b6a648b43e5670aa2e4bb985914eaeb2d2"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "slab"
 version = "0.4.2"
@@ -603,10 +641,12 @@ dependencies = [
  "byteorder",
  "clap",
  "crc32c",
+ "duct",
  "fixedbitset",
  "flate2",
  "futures",
  "io-uring",
+ "json",
  "libc",
  "nix",
  "nom",