fix(rust): disable proc-macro-disabled diagnostic

The default config disables a bunch of proc macros, but that causes a
huge diagnostic to be shown by default for those proc macros. This
disables that diagnostic by default.

Related
- https://github.com/rust-lang/rust-analyzer/issues/18414
- https://github.com/mrcjkb/rustaceanvim/discussions/482
- https://github.com/LazyVim/LazyVim/discussions/5638

lua/lazyvim/plugins/extras/lang/rust.lua

@@ -83,6 +83,9 @@ return {
             -- Enable diagnostics if using rust-analyzer
             diagnostics = {
               enable = diagnostics == "rust-analyzer",
+              disabled = {
+                "proc-macro-disabled",
+              },
             },
             procMacro = {
               enable = true,