Remove pub on some command internals (#14636)

Stumbled over unnecessary `pub` `fn action` and `struct Arguments` when
reworking `into bits` in #14634

Stuff like this should be local until proven otherwise and then named
approrpiately.

crates/nu-command/src/platform/ansi/strip.rs

@@ -4,7 +4,7 @@ use nu_cmd_base::input_handler::{operate, CmdArgument};
 use nu_engine::command_prelude::*;
 use nu_protocol::Config;
 
-pub struct Arguments {
+struct Arguments {
     cell_paths: Option<Vec<CellPath>>,
     config: Arc<Config>,
 }