Remove editor::Cancel binding from vim

When you hit <escape> in the command palette, it first editor::Cancel
because the command palette is also a focused editor; this binding was
catching before the `menu::Cancel` that you probably want.

From looking at the uses of editor::Cancel it seems like the only way to
trigger this is with <escape> in an editor. Rather than trying to hook
into the existing editor cancel and add vim-specific behaviour, we'll
instead take responsibility for binding directly to <escape> when
necessary.

Fixes: zed-industries/community#1347

crates/vim/src/test/vim_test_context.rs

@@ -21,12 +21,14 @@ impl<'a> VimTestContext<'a> {
         cx.update(|cx| {
             search::init(cx);
             crate::init(cx);
+            command_palette::init(cx);
         });
 
         cx.update(|cx| {
             cx.update_global(|store: &mut SettingsStore, cx| {
                 store.update_user_settings::<VimModeSetting>(cx, |s| *s = Some(enabled));
             });
+            settings::KeymapFile::load_asset("keymaps/default.json", cx).unwrap();
             settings::KeymapFile::load_asset("keymaps/vim.json", cx).unwrap();
         });