Reuse s:edit_cmds for a tag in the file already shown

The tag branch edited the file unconditionally, unlike every other kind, so
showing a tag in the window's own buffer reloaded it and reset the undo
history. s:tags_sink does not re-edit either.

autoload/fzf/vim.vim

@@ -723,8 +723,8 @@ function! s:goto_entry(winid, bufnr, dir, kind, entry) abort
     if empty(excmd) || !filereadable(path)
       return
     endif
-    let cmds = ['keepalt keepjumps hide edit '.s:escape(path),
-          \ 'keepjumps '.excmd, 'normal! ^zvzz']
+    let cmds = s:edit_cmds(a:winid, path)
+          \ + ['keepjumps '.excmd, 'normal! ^zvzz']
   elseif a:kind ==# 'btags'
     let parts = split(entry, "\t")
     if len(parts) < 3 || !bufexists(a:bufnr)