Luis Javier Merino authored May 29, 2022 and Tomaz Canabrava committed Jul 03, 2022

- Only recognize SGR 38/48 semicolon forms if there are no subparams for
  that parameter.
- Add some tests for SGR 38 parsing.
- Add comment about ignoring 0x7F in Ground state.
- Fix off-by-one when collect()ing intermediates.

Plus another one triggered by code quality warnings:
- Don't test for impossible conditions.