Implement module formatting using JoinNodesBuilder (#4808)

* Implement module formatting using JoinNodesBuilder

This uses JoinNodesBuilder to implement module formatting for #4800

See the snapshots for the changed behaviour. See one PR up for a CLI that i used to verify the trailing new line behaviour

crates/ruff_python_formatter/src/module/mod_module.rs

@@ -1,8 +1,7 @@
-use crate::AsFormat;
-use crate::{FormatNodeRule, PyFormatter};
+use crate::statement::suite::SuiteLevel;
+use crate::{AsFormat, FormatNodeRule, PyFormatter};
 use ruff_formatter::prelude::hard_line_break;
 use ruff_formatter::{write, Buffer, FormatResult};
-
 use rustpython_parser::ast::ModModule;
 
 #[derive(Default)]
@@ -10,9 +9,13 @@ pub struct FormatModModule;
 
 impl FormatNodeRule<ModModule> for FormatModModule {
     fn fmt_fields(&self, item: &ModModule, f: &mut PyFormatter) -> FormatResult<()> {
-        for stmt in &item.body {
-            write!(f, [stmt.format(), hard_line_break()])?;
-        }
-        Ok(())
+        write!(
+            f,
+            [
+                item.body.format().with_options(SuiteLevel::TopLevel),
+                // Trailing newline at the end of the file
+                hard_line_break()
+            ]
+        )
     }
 }