ruby: Fix solargraph completion highlighting (#11825)

Hi. This pull request fixes a small error with `solargraph` completions
to make them more detailed. It removes the nested match expression to
resolve the problem with highlighting the completion items and their
signatures with the return type as well. Thanks.

See screenshots below.

Release Notes:

- N/A

| Before  | After |
| ------------- | ------------- |
| ![CleanShot 2024-05-14 at 23 23
00@2x](https://github.com/zed-industries/zed/assets/1894248/4ea1fa41-1189-4607-8aea-547c27229a18)
| ![CleanShot 2024-05-14 at 23 29
30@2x](https://github.com/zed-industries/zed/assets/1894248/3c7be39a-2c7b-4662-8519-8c258c049cfa)
|

extensions/ruby/src/language_servers/solargraph.rs

@@ -20,8 +20,6 @@ impl Solargraph {
     }
 
     pub fn label_for_completion(&self, completion: Completion) -> Option<CodeLabel> {
-        match completion.kind? {
-            CompletionKind::Method => {
         let highlight_name = match completion.kind? {
             CompletionKind::Class | CompletionKind::Module => "type",
             CompletionKind::Constant => "constant",
@@ -44,8 +42,7 @@ impl Solargraph {
         };
 
         let len = completion.label.len();
-                let name_span =
-                    CodeLabelSpan::literal(completion.label, Some(highlight_name.to_string()));
+        let name_span = CodeLabelSpan::literal(completion.label, Some(highlight_name.to_string()));
 
         Some(CodeLabel {
             code: Default::default(),
@@ -61,9 +58,6 @@ impl Solargraph {
             filter_range: (0..len).into(),
         })
     }
-            _ => None,
-        }
-    }
 
     pub fn label_for_symbol(&self, symbol: Symbol) -> Option<CodeLabel> {
         let name = &symbol.name;