swayfmt: fix indentation after where in fn (#5468) (#5578)

## Description
This is a small fix to match the indentation for opening brace after a
where clause is seen. This should fix #5468

cc: @Braqzen 

The change is near trivial.
## Checklist

- [x] I have linked to any relevant issues.
- [x] 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).
- [x] 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.
- [x] 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).
- [x] I have requested a review from the relevant team or maintainers.

Co-authored-by: Kaya Gökalp <kaya.gokalp@fuel.sh>
Co-authored-by: Sophie Dankel <47993817+sdankel@users.noreply.github.com>

sway-lib-std/src/storage/storage_map.sw

@@ -53,7 +53,7 @@ where
     pub fn insert(self, key: K, value: V)
     where
         K: Hash,
-{
+    {
         let key = sha256((key, self.field_id));
         write::<V>(key, 0, value);
     }
@@ -87,7 +87,7 @@ where
     pub fn get(self, key: K) -> StorageKey<V>
     where
         K: Hash,
-{
+    {
         StorageKey::<V>::new(
             sha256((key, self.field_id)),
             0,
@@ -129,7 +129,7 @@ where
     pub fn remove(self, key: K) -> bool
     where
         K: Hash,
-{
+    {
         let key = sha256((key, self.slot));
         clear::<V>(key, 0)
     }
@@ -180,7 +180,7 @@ where
     pub fn try_insert(self, key: K, value: V) -> Result<V, StorageMapError<V>>
     where
         K: Hash,
-{
+    {
         let key = sha256((key, self.field_id));
 
         let val = read::<V>(key, 0);

swayfmt/src/items/item_fn/mod.rs

@@ -83,7 +83,8 @@ impl CurlyBrace for ItemFn {
         let open_brace = Delimiter::Brace.as_open_char();
         match formatter.shape.code_line.has_where_clause {
             true => {
-                write!(line, "{open_brace}")?;
+                let indent_str = formatter.indent_to_str()?;
+                write!(line, "{indent_str}{open_brace}")?;
                 formatter.shape.code_line.update_where_clause(false);
             }
             false => {

swayfmt/tests/mod.rs

@@ -2903,3 +2903,37 @@ pub fn from_be_bytes(bytes: [u8; 32]) -> Self {
 "#,
     );
 }
+
+#[test]
+fn impl_func_where() {
+    check(
+        r#"library;
+
+        impl<K, V> Foo<Bar<K, V>>
+        where
+            K: Hash,
+        {
+            pub fn baz(self, _: K, _: V)
+            where
+                K: Hash,
+        {
+                debug();
+            }
+        }
+    "#,
+        r#"library;
+
+impl<K, V> Foo<Bar<K, V>>
+where
+    K: Hash,
+{
+    pub fn baz(self, _: K, _: V)
+    where
+        K: Hash,
+    {
+        debug();
+    }
+}
+"#,
+    );
+}