Remove it expansion (#2701)

* Remove it-expansion, take 2

* Cleanup

* silly update to test CI

crates/nu-cli/tests/commands/prepend.rs

@@ -21,7 +21,6 @@ fn adds_a_row_to_the_beginning() {
                 | lines
                 | prepend "pollo loco"
                 | nth 0
-                | echo $it
                 "#
         ));