Run test_curses_interactive in CI

[geofft]

From src/verify_distribution.py:

    @unittest.skipIf(os.name == "nt", "curses not available on Windows")
    @unittest.skipIf("TERM" not in os.environ, "TERM not set")
    def test_curses_interactive(self):
        import curses
        
        curses.initscr()
        curses.endwin()

I believe this is getting skipped in GitHub Actions, but it's probably enough to run this inside a pty, we just need to set TERM to some valid value. If not we can try to run it in a real headless terminal like screen/tmux or something (just make sure we report the exit status correctly).