Add VIM_KEYMAP_PATH constant (#23228)

Deduplicates 2 occurrences

Release Notes:

- N/A

crates/settings/src/settings.rs

@@ -82,8 +82,10 @@ pub fn default_keymap() -> Cow<'static, str> {
     asset_str::<SettingsAssets>(DEFAULT_KEYMAP_PATH)
 }
 
+pub const VIM_KEYMAP_PATH: &str = "keymaps/vim.json";
+
 pub fn vim_keymap() -> Cow<'static, str> {
-    asset_str::<SettingsAssets>("keymaps/vim.json")
+    asset_str::<SettingsAssets>(VIM_KEYMAP_PATH)
 }
 
 pub fn initial_user_settings_content() -> Cow<'static, str> {