debugger: Remove fake adapter and un-gate GDB (#27557)

This is a clean-up PR in anticipation of introduction of Debugger
Registry. I wanna get rid of DebugAdapterKind (or rather, it being an
enum).
Release Notes:

- N/A

---------

Co-authored-by: Anthony Eid <hello@anthonyeid.me>
Co-authored-by: Anthony <anthony@zed.dev>

crates/debugger_ui/src/debugger_panel.rs

@@ -3,8 +3,8 @@ use anyhow::{anyhow, Result};
 use collections::HashMap;
 use command_palette_hooks::CommandPaletteFilter;
 use dap::{
-    client::SessionId, debugger_settings::DebuggerSettings, ContinuedEvent, DebugAdapterConfig,
-    LoadedSourceEvent, ModuleEvent, OutputEvent, StoppedEvent, ThreadEvent,
+    client::SessionId, debugger_settings::DebuggerSettings, ContinuedEvent, LoadedSourceEvent,
+    ModuleEvent, OutputEvent, StoppedEvent, ThreadEvent,
 };
 use futures::{channel::mpsc, SinkExt as _};
 use gpui::{
@@ -19,6 +19,7 @@ use project::{
 use rpc::proto::{self};
 use settings::Settings;
 use std::{any::TypeId, path::PathBuf};
+use task::DebugTaskDefinition;
 use terminal_view::terminal_panel::TerminalPanel;
 use ui::prelude::*;
 use util::ResultExt;
@@ -52,7 +53,7 @@ pub struct DebugPanel {
     project: WeakEntity<Project>,
     workspace: WeakEntity<Workspace>,
     _subscriptions: Vec<Subscription>,
-    pub(crate) last_inert_config: Option<DebugAdapterConfig>,
+    pub(crate) last_inert_config: Option<DebugTaskDefinition>,
 }
 
 impl DebugPanel {