chore: update the rust-version key in Cargo.toml (#2193)

Author: SteveLauC

Cargo.toml

@@ -3,7 +3,7 @@ name        = "nix"
 description = "Rust friendly bindings to *nix APIs"
 edition     = "2021"
 version     = "0.27.1"
-rust-version = "1.65"
+rust-version = "1.69"
 authors     = ["The nix-rust Project Developers"]
 repository  = "https://github.com/nix-rust/nix"
 license     = "MIT"