Table help rendering (#13182)

# Description

Mostly fixes #13149 with much of the credit to @fdncred.

This PR runs `table --expand` against `help` example results. This is
essentially the same fix that #13146 was for `std help`.

It also changes the shape of the result for the `table --expand`
example, as it was hardcoded wrong.

~Still needed is a fix for the `table --collapse` example.~ Note that
this is also still a bug in `std help` that I didn't noticed before.

# User-Facing Changes

Certain tables are now rendered correctly in the help examples for:

* `table`
* `zip`
* `flatten`
* And almost certainly others

# Tests + Formatting

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>

crates/nu-command/src/viewers/table.rs

@@ -170,7 +170,10 @@ impl Command for Table {
                     }),
                     Value::test_record(record! {
                         "a" =>  Value::test_int(3),
-                        "b" =>  Value::test_int(4),
+                        "b" =>  Value::test_list(vec![
+                            Value::test_int(4),
+                            Value::test_int(4),
+                        ])
                     }),
                 ])),
             },
@@ -184,7 +187,10 @@ impl Command for Table {
                     }),
                     Value::test_record(record! {
                         "a" =>  Value::test_int(3),
-                        "b" =>  Value::test_int(4),
+                        "b" =>  Value::test_list(vec![
+                            Value::test_int(4),
+                            Value::test_int(4),
+                        ])
                     }),
                 ])),
             },