This reverts commit 6c089b2af5d8d98f66b27b67f70958f520820a76.
This was causing the test test_help_run_hides_options from TestHelp.py to
fail on Linux and Windows (but the test succeeds on macOS). The decision
to print option information is determined by CommandObjectAlias::IsDashDashCommand
which was changed, but only by replacing an inline string constant with a const char *
CommandInterpreter::g_argument which has the same string value. I can't see why this
would fail, I'll have to spin up a vm to see if I can repo there.