[clients] Add missing require statements (#2256)

Author: leungbk

clients/lsp-html.el

@@ -20,6 +20,8 @@
 
 ;;; Code:
 
+(require 'lsp-mode)
+
 (defgroup lsp-html nil
   "LSP support for HTML, using vscode-html-languageserver."
   :group 'lsp-mode

clients/lsp-racket.el

@@ -24,6 +24,9 @@
 
 ;;; Code:
 
+(require 'ht)
+(require 'lsp-mode)
+
 
 ;; racket-langserver