Remove explicit tokio (#1470)

Author: CriesofCarrots

Cargo.lock

@@ -13,7 +13,7 @@ test-bpf = []
 [dependencies]
 num-derive = "0.3"
 num-traits = "0.2"
-solana-program = "1.5.14"
+solana-program = "1.6.1"
 spl-token = { version = "3.0", path = "../../token/program", features = [ "no-entrypoint" ] }
 thiserror = "1.0"
 uint = "0.8"
@@ -22,8 +22,7 @@ borsh = "0.8.2"
 
 [dev-dependencies]
 solana-program-test = "1.6.1"
-solana-sdk = "1.5.14"
-tokio = { version = "1.3.0", features = ["macros"]}
+solana-sdk = "1.6.1"
 
 [lib]
 crate-type = ["cdylib", "lib"]