Advertise utf-32 support (#3958)

Author: matklad

lsp-mode.el

@@ -3549,7 +3549,8 @@ disappearing, unset all the variables related to it."
 (defun lsp--client-capabilities (&optional custom-capabilities)
   "Return the client capabilities appending CUSTOM-CAPABILITIES."
   (append
-   `((workspace . ((workspaceEdit . ((documentChanges . t)
+   `((general . ((positionEncodings . ["utf-32", "utf-16"])))
+     (workspace . ((workspaceEdit . ((documentChanges . t)
                                      (resourceOperations . ["create" "rename" "delete"])))
                    (applyEdit . t)
                    (symbol . ((symbolKind . ((valueSet . ,(apply 'vector (number-sequence 1 26)))))))