util: Fall back to cmd if we can't find powershell on the system (#42204)

Closes https://github.com/zed-industries/zed/issues/42165

Release Notes:

- Fixed trying to use powershell for commands when its not installed on
the system

crates/util/src/shell_env.rs

@@ -208,7 +208,6 @@ async fn capture_windows(
         String::from_utf8_lossy(&output.stdout),
         String::from_utf8_lossy(&output.stderr),
     );
-    // "cmd" "/c" "cd \'C:\\Workspace\\salsa\\\'; \'C:\\Workspace\\zed\\zed\\target\\debug\\zed.exe\' --printenv"
     let env_output = String::from_utf8_lossy(&output.stdout);
 
     // Parse the JSON output from zed --printenv