runtime(vim): Update syntax file, fix missing for highlight (#13668)

Fix highlighting of :for command.  Link the vimFor syntax group to the
vimCommand highlight group.

Error introduced in commit f686921

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index 5697ce3..c1706e0 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -938,6 +938,7 @@
  hi def link vimFuncEcho	vimCommand
  hi def link vimHiCtermul	vimHiTerm
  hi def link vimFold	Folded
+ hi def link vimFor	vimCommand
  hi def link vimFTCmd	vimCommand
  hi def link vimFTOption	vimSynType
  hi def link vimFuncKey	vimCommand