feat(cmp): disable item.menu for Rust filetypes (#3858)

## What is this PR for?
Tries to improve aesthetics for `nvim-cmp` in Rust by disabling
`item.menu` since it contains the `return` types that take up too much
space.
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  why we should accept this pull request. -->

## Does this PR fix an existing issue?
Fixes #3855
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  If this PR fixes any issues, please link to the issue here.
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## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

lua/lazyvim/plugins/coding.lua

@@ -49,11 +49,14 @@ return {
           { name = "buffer" },
         }),
         formatting = {
-          format = function(_, item)
+          format = function(entry, item)
             local icons = LazyVim.config.icons.kinds
             if icons[item.kind] then
               item.kind = icons[item.kind] .. item.kind
             end
+            if entry.context.filetype == "rust" then
+              item.menu = nil
+            end
             return item
           end,
         },