Add newline to empty list output (#14758)

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Adds a newline to the empty list output. Fixes #14748.

This does not affect the `[empty list]` text output in the REPL, just
the `print` output (to be honest, I'm not certain why, but I'm guessing
the REPL was adding an extra newline somewhere to compensate). The
`bytes.push('\n')` replicates the code from the below
`convert_table_to_output` function, which is bypassed for empty lists.

Before:
```nushell
[]
# => ╭────────────╮
# => │ empty list │
# => ╰────────────╯
print ([]) text
# => ╭────────────╮
# => │ empty list │
# => ╰────────────╯text
```

After:
```nushell
[]
# => ╭────────────╮
# => │ empty list │
# => ╰────────────╯
print ([]) text
# => ╭────────────╮
# => │ empty list │
# => ╰────────────╯
# => text
```

# User-Facing Changes
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* Fixes "empty list" placeholder text output when using the `print`
command

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N/A

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

@@ -885,7 +885,9 @@ impl Iterator for PagingTableCreator {
                     &self.engine_state,
                     &self.stack,
                 );
-                Some(Ok(result.into_bytes()))
+                let mut bytes = result.into_bytes();
+                bytes.push(b'\n');
+                Some(Ok(bytes))
             } else {
                 None
             };