[parser] bare_statement_for - move remember right after keyword

forming sequence `KW_FOR remember`.

Non-terminal `remember` is empty non-terminal with action starting
new full lexical scope. Such empty non-terminals, when used in
multiple branches, will generate shift/reduce conflict when not
appearing after distinguishable sequence of terminals.

Change formalizes `KW_FOR` as a keyword starting new lexical scope.

Author: Branislav Zahradník