Add assertion context manager to TestAppContext and convert existing vim tests to use neovim backed test context

crates/vim/src/normal/change.rs

@@ -79,7 +79,7 @@ mod test {
 
     use crate::{
         state::Mode,
-        test_contexts::{NeovimBackedTestContext, VimTestContext},
+        test::{NeovimBackedTestContext, VimTestContext},
     };
 
     #[gpui::test]

crates/vim/src/normal/delete.rs

@@ -96,7 +96,7 @@ pub fn delete_object(vim: &mut Vim, object: Object, around: bool, cx: &mut Mutab
 mod test {
     use indoc::indoc;
 
-    use crate::{state::Mode, test_contexts::VimTestContext};
+    use crate::{state::Mode, test::VimTestContext};
 
     #[gpui::test]
     async fn test_delete_h(cx: &mut gpui::TestAppContext) {