install tokio as a dependency

Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "addr2line"
@@ -328,6 +328,7 @@ version = "0.1.0"
 dependencies = [
  "diesel",
  "diesel-async",
+ "tokio",
 ]
 
 [[package]]
@@ -734,9 +735,21 @@ dependencies = [
  "mio",
  "pin-project-lite",
  "socket2",
+ "tokio-macros",
  "windows-sys",
 ]
 
+[[package]]
+name = "tokio-macros"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e06d43f1345a3bcd39f6a56dbb7dcab2ba47e68e8ac134855e7e2bdbaf8cab8"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "tokio-postgres"
 version = "0.7.13"

Cargo.toml

@@ -8,3 +8,4 @@ edition = "2021"
 [dependencies]
 diesel = { version = "2.2.8", features = ["postgres"] }
 diesel-async = { version = "0.5.2", features = ["postgres"] }
+tokio = { version = "1.44.1", features = ["rt-multi-thread", "macros"] }