[ts-command-line] The argparse library allows arbitrary abbreviations, which causes confusion

[octogonz]

Someone was recently asked to type this command:

rush --debug update -p --full

...but they accidentally typed this:

rush update -p --full --debug

Expected: According to the design of ts-command-line, this should have reported an error, since --debug is a global option, NOT an option of the rush update subcommand.

What actually happens: Instead, the command silently succeeds, but confusingly behaves as if this was typed:

rush update -p --full --debug-package-manager

The reason is that argparse has an obscure feature that allows any option to be shortened (e.g. --debug-pac instead of --debug-package-manager), as long as it doesn't cause ambiguity. But this convenience only looks for ambiguity within a single parser block.