Merge branch 'es/worktree-add' into maint

* es/worktree-add:
  worktree: usage: denote <branch> as optional with 'add'

builtin/worktree.c

@@ -10,7 +10,7 @@
 #include "refs.h"
 
 static const char * const worktree_usage[] = {
-	N_("git worktree add [<options>] <path> <branch>"),
+	N_("git worktree add [<options>] <path> [<branch>]"),
 	N_("git worktree prune [<options>]"),
 	NULL
 };