cx.background_executor().spawn(...) -> cx.background_spawn(...) (#25103)

Done automatically with

> ast-grep -p '$A.background_executor().spawn($B)' -r
'$A.background_spawn($B)' --update-all --globs "\!crates/gpui"

Followed by:

* `cargo fmt`
* Unexpected need to remove some trailing whitespace.
* Manually adding imports of `gpui::{AppContext as _}` which provides
`background_spawn`
* Added `AppContext as _` to existing use of `AppContext`

Release Notes:

- N/A

crates/journal/src/journal.rs

@@ -2,7 +2,7 @@ use anyhow::Result;
 use chrono::{Datelike, Local, NaiveTime, Timelike};
 use editor::scroll::Autoscroll;
 use editor::Editor;
-use gpui::{actions, App, Context, Window};
+use gpui::{actions, App, AppContext as _, Context, Window};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use settings::{Settings, SettingsSources};
@@ -87,7 +87,7 @@ pub fn new_journal_entry(workspace: &Workspace, window: &mut Window, cx: &mut Ap
     let now = now.time();
     let entry_heading = heading_entry(now, &settings.hour_format);
 
-    let create_entry = cx.background_executor().spawn(async move {
+    let create_entry = cx.background_spawn(async move {
         std::fs::create_dir_all(month_dir)?;
         OpenOptions::new()
             .create(true)