fix: no suggest ref match when expected generic ref

Example
---
```rust
fn foo<T>(s: &T) {}
fn main() {
    let ssss = &mut 2i32;
    foo($0);
}
```

**Before this PR**

```text
lc ssss &mut i32 [type_could_unify+local]
lc &ssss [type+local]
md core::  []
fn foo(…) fn(&T) []
fn &foo(…) [type]
fn main() fn() []
fn &main() [type]
```

**After this PR**

```text
lc ssss &mut i32 [type_could_unify+local]
md core::  []
fn foo(…) fn(&T) []
fn &foo(…) [type]
fn main() fn() []
fn &main() [type]
```

Author: A4-Tacks

crates/ide-completion/src/render.rs

@@ -717,12 +717,13 @@ fn compute_ref_match(
     ctx: &CompletionContext<'_, '_>,
     completion_ty: &hir::Type<'_>,
 ) -> Option<CompletionItemRefMode> {
+    if compute_type_match(ctx, completion_ty).is_some() {
+        return None;
+    }
     let expected_type = ctx.expected_type.as_ref()?;
     let expected_without_ref = expected_type.remove_ref();
     let completion_without_ref = completion_ty.remove_ref();
-    if expected_type.could_unify_with(ctx.db, completion_ty) {
-        return None;
-    }
+
     if let Some(expected_without_ref) = &expected_without_ref
         && (completion_without_ref.is_none()
             || completion_ty.could_unify_with(ctx.db, expected_without_ref))
@@ -2976,6 +2977,24 @@ fn main() {
                 fn main() fn() []
             "#]],
         );
+        check_relevance(
+            r#"
+//- minicore: deref
+fn foo<T>(s: &T) {}
+fn main() {
+    let ssss = &mut 2i32;
+    foo($0);
+}
+            "#,
+            expect![[r#"
+                lc ssss &mut i32 [type_could_unify+local]
+                md core::  []
+                fn foo(…) fn(&T) []
+                fn &foo(…) [type]
+                fn main() fn() []
+                fn &main() [type]
+            "#]],
+        );
     }
 
     #[test]