Add rt-multi-thread feature to tokio

Cargo.lock

@@ -858,6 +858,12 @@ dependencies = [
  "allocator-api2",
 ]
 
+[[package]]
+name = "hermit-abi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d231dfb89cfffdbc30e7fc41579ed6066ad03abda9e567ccafae602b97ec5024"
+
 [[package]]
 name = "hmac"
 version = "0.12.1"
@@ -1687,6 +1693,16 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51d515d32fb182ee37cda2ccdcb92950d6a3c2893aa280e540671c2cd0f3b1d9"
 
+[[package]]
+name = "num_cpus"
+version = "1.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4161fcb6d602d4d2081af7c3a45852d875a03dd337a6bfdd6e06407b61342a43"
+dependencies = [
+ "hermit-abi",
+ "libc",
+]
+
 [[package]]
 name = "object"
 version = "0.32.2"
@@ -2543,6 +2559,7 @@ dependencies = [
  "bytes",
  "libc",
  "mio",
+ "num_cpus",
  "pin-project-lite",
  "socket2",
  "tokio-macros",