Enable clippy::cast_abs_to_unsigned (#8912)

Thankfully this one is a simple, single change that also prevents
overflow in the `abs()`

Cargo.toml

@@ -372,7 +372,6 @@ almost_complete_range = "allow"
 arc_with_non_send_sync = "allow"
 await_holding_lock = "allow"
 borrowed_box = "allow"
-cast_abs_to_unsigned = "allow"
 derive_ord_xor_partial_ord = "allow"
 eq_op = "allow"
 let_underscore_future = "allow"

crates/terminal/src/mappings/mouse.rs

@@ -107,7 +107,7 @@ pub fn scroll_report(
 pub fn alt_scroll(scroll_lines: i32) -> Vec<u8> {
     let cmd = if scroll_lines > 0 { b'A' } else { b'B' };
 
-    let mut content = Vec::with_capacity(scroll_lines.abs() as usize * 3);
+    let mut content = Vec::with_capacity(scroll_lines.unsigned_abs() as usize * 3);
     for _ in 0..scroll_lines.abs() {
         content.push(0x1b);
         content.push(b'O');