docs: Add docs for hover_popover_delay and update hover delay (#30620)

- Add docs for `hover_popover_delay`.
- Set `hover_popover_delay` to `300` from `350` which matches [VSCode's
hover
delay](https://github.com/microsoft/vscode/blob/ed48873ba23ae0a06a0eafb328ca1ce62b7d4b72/src/vs/editor/common/config/editorOptions.ts#L2219).

Release Notes:

- Added `hover_popover_delay` to settings which determines time to wait
in milliseconds before showing the informational hover box.

crates/editor/src/editor_settings.rs

@@ -369,9 +369,9 @@ pub struct EditorSettingsContent {
     ///
     /// Default: true
     pub hover_popover_enabled: Option<bool>,
-    /// Time to wait before showing the informational hover box
+    /// Time to wait in milliseconds before showing the informational hover box.
     ///
-    /// Default: 350
+    /// Default: 300
     pub hover_popover_delay: Option<u64>,
     /// Toolbar related settings
     pub toolbar: Option<ToolbarContent>,