pin to rust v1.65 (#7249)

# Description

This fixes the compilation problems with `aarch64-apple-darwin` on rust
1.64 as well as the `zstd` problems. We recently found out that `zstd`
pinned to 1.65.



# User-Facing Changes

N/A

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.

crates/nu-system/src/macos.rs

@@ -325,7 +325,7 @@ impl ProcessInfo {
     pub fn command(&self) -> String {
         if let Some(path) = &self.curr_path {
             if !path.cmd.is_empty() {
-                path.cmd.join(" ").replace('\n', " ").replace('\t', " ")
+                path.cmd.join(" ").replace(['\n', '\t'], " ")
             } else {
                 String::new()
             }