fixes a bug in OSC9;9 execution (#12994)

# Description

This fixes a bug in the `OSC 9;9` functionality where the path wasn't
being constructed properly and therefore wasn't getting set right for
things like "Duplicate Tab" in Windows Terminal. Thanks to @Araxeus for
finding it.

Related to https://github.com/nushell/nushell/issues/10166

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crates/nu-cli/src/repl.rs

@@ -1110,9 +1110,9 @@ fn run_shell_integration_osc9_9(engine_state: &EngineState, stack: &mut Stack, u
         let start_time = Instant::now();
 
         // Otherwise, communicate the path as OSC 9;9 from ConEmu (often used for spawning new tabs in the same dir)
+        // This is helpful in Windows Terminal with Duplicate Tab
         run_ansi_sequence(&format!(
-            "\x1b]9;9;{}{}\x1b\\",
-            if path.starts_with('/') { "" } else { "/" },
+            "\x1b]9;9;{}\x1b\\",
             percent_encoding::utf8_percent_encode(&path, percent_encoding::CONTROLS)
         ));