Remove ruby debug adapter (#33541)

Now that the extension version has been bumped we can remove our in-tree
one to avoid having duplicate debug adapters.

Release Notes:

- The ruby debug adapter has been moved to the [ruby
extension](https://github.com/zed-extensions/ruby), if you have any
saved debug scenarios you'll need to change `"adapter": "Ruby"` to
`"adapter": "rdbg"`.

crates/task/src/vscode_debug_format.rs

@@ -93,7 +93,7 @@ fn task_type_to_adapter_name(task_type: &str) -> String {
         "php" => "PHP",
         "cppdbg" | "lldb" => "CodeLLDB",
         "debugpy" => "Debugpy",
-        "rdbg" => "Ruby",
+        "rdbg" => "rdbg",
         _ => task_type,
     }
     .to_owned()