gh-92446: Improve argparse choices docs; revert bad change to lzma docs (#94627)

Based on the definition of the collections.abc classes, it is more accurate to use "sequence" instead of "container" when describing argparse choices.

A previous attempt at fixing this in #92450 was mistaken; this PR reverts that change.

Co-authored-by: Shantanu <12621235+hauntsaninja@users.noreply.github.com>