Merge branch 'es/restore-staged-from-head-by-default'

"git restore --staged --worktree" now defaults to take the contents
out of "HEAD", instead of erring out.

* es/restore-staged-from-head-by-default:
  restore: default to HEAD when combining --staged and --worktree

diff --cc Documentation/git-restore.txt
Simple merge

diff --cc builtin/checkout.c
Simple merge