Use built-in is_terminal instead of is_terminal::is_terminal (#9550)

# Description
This PR tries to remove ~atty~ is-terminal from the entire code base,
since ~[atty is
unmaintained](https://rustsec.org/advisories/RUSTSEC-2021-0145) and~
[`is_terminal` has been
stabilized](https://blog.rust-lang.org/2023/06/01/Rust-1.70.0.html#isterminal)
in rust 1.70.0.

cc @fdncred 

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src/terminal.rs

@@ -1,11 +1,11 @@
 #[cfg(unix)]
 pub(crate) fn acquire_terminal(interactive: bool) {
-    use is_terminal::IsTerminal;
     use nix::{
         errno::Errno,
         sys::signal::{signal, SigHandler, Signal},
         unistd,
     };
+    use std::io::IsTerminal;
 
     if interactive && std::io::stdin().is_terminal() {
         // see also: https://www.gnu.org/software/libc/manual/html_node/Initializing-the-Shell.html