Remove futures from debugger ui crate

Cargo.lock

@@ -3776,7 +3776,6 @@ dependencies = [
  "dap",
  "editor",
  "env_logger 0.11.6",
- "futures 0.3.31",
  "fuzzy",
  "gpui",
  "language",

crates/debugger_ui/Cargo.toml

@@ -25,7 +25,6 @@ collections.workspace = true
 command_palette_hooks.workspace = true
 dap.workspace = true
 editor.workspace = true
-futures.workspace = true
 fuzzy.workspace = true
 gpui.workspace = true
 language.workspace = true