refactor: item_configurable test to use test_macros (FuelLabs#4365)

## Description

Just a small cleanup - Code deletion is delicious

## Checklist

- [ ] I have linked to any relevant issues.
- [ ] I have commented my code, particularly in hard-to-understand
areas.
- [ ] I have updated the documentation where relevant (API docs, the
reference, and the Sway book).
- [ ] I have added tests that prove my fix is effective or that my
feature works.
- [ ] I have added (or requested a maintainer to add) the necessary
`Breaking*` or `New Feature` labels where relevant.
- [ ] I have done my best to ensure that my PR adheres to [the Fuel Labs
Code Review
Standards](https://github.com/FuelLabs/rfcs/blob/master/text/code-standards/external-contributors.md).
- [ ] I have requested a review from the relevant team or maintainers.

swayfmt/src/items/item_configurable/tests.rs

@@ -1,68 +1,9 @@
 use forc_tracing::{println_green, println_red};
 use paste::paste;
 use prettydiff::{basic::DiffOp, diff_lines};
+use test_macros::fmt_test_item;
 
-macro_rules! fmt_test {
-    ($scope:ident $desired_output:expr, $($name:ident $y:expr),+) => {
-        fmt_test_inner!($scope $desired_output,
-                                $($name $y)+
-                                ,
-                                remove_trailing_whitespace format!("{} \n\n\t ", $desired_output).as_str(),
-                                remove_beginning_whitespace format!("  \n\t{}", $desired_output).as_str(),
-                                identity $desired_output, /* test return is valid */
-                                remove_beginning_and_trailing_whitespace format!("  \n\t  {} \n\t   ", $desired_output).as_str()
-                       );
-    };
-}
-
-macro_rules! fmt_test_inner {
-    ($scope:ident $desired_output:expr, $($name:ident $y:expr),+) => {
-        $(
-        paste! {
-            #[test]
-            fn [<$scope _ $name>] () {
-                let formatted_code = crate::parse::parse_format::<sway_ast::ItemConfigurable>($y);
-                let changeset = diff_lines(&formatted_code, $desired_output);
-                let diff = changeset.diff();
-                let count_of_updates = diff.len();
-                if count_of_updates != 0 {
-                    println!("FAILED: {count_of_updates} diff items.");
-                }
-                for diff in diff {
-                    match diff {
-                        DiffOp::Equal(old) => {
-                            for o in old {
-                                println!("{}", o)
-                            }
-                        }
-                        DiffOp::Insert(new) => {
-                            for n in new {
-                                println_green(&format!("+{}", n));
-                            }
-                        }
-                        DiffOp::Remove(old) => {
-                            for o in old {
-                                println_red(&format!("-{}", o));
-                            }
-                        }
-                        DiffOp::Replace(old, new) => {
-                            for o in old {
-                                println_red(&format!("-{}", o));
-                            }
-                            for n in new {
-                                println_green(&format!("+{}", n));
-                            }
-                        }
-                    }
-                }
-                assert_eq!(&formatted_code, $desired_output)
-            }
-        }
-    )+
-}
-}
-
-fmt_test!( configurables
+fmt_test_item!( configurables
 "configurable {
     C0: bool = true,
     C1: u64 = 42,