Fix running vim tests with --features neovim (#36014)

This was broken incidentally in
https://github.com/zed-industries/zed/pull/33417

A better fix would be to fix app shutdown to take control of the
executor so that we *can* run
foreground tasks; but that is a bit fiddly (draft #36015) 

Release Notes:

- N/A

crates/vim/src/test/vim_test_context.rs

@@ -15,6 +15,7 @@ impl VimTestContext {
         if cx.has_global::<VimGlobals>() {
             return;
         }
+        env_logger::try_init().ok();
         cx.update(|cx| {
             let settings = SettingsStore::test(cx);
             cx.set_global(settings);