workaround neovim bug

sets/nvim.nix

@@ -175,6 +175,16 @@ lib.setAttrByPath setPath (
             { name = 'cmdline' }
           })
         })
+
+        for _, method in ipairs({ 'textDocument/diagnostic', 'workspace/diagnostic' }) do
+            local default_diagnostic_handler = vim.lsp.handlers[method]
+            vim.lsp.handlers[method] = function(err, result, context, config)
+                if err ~= nil and err.code == -32802 then
+                    return
+                end
+                return default_diagnostic_handler(err, result, context, config)
+            end
+        end
       end
     '';
   }