m.code: fix ANSI lexer compatibility with Pygments 2.12+.
m.code: fix ANSI lexer compatibility with Pygments 2.12+.

I'm still pinned on an older version because of the significant
difference in output, but it shoulnd't crash at least.

mosra/m.css,mosra/m.css,mosra/m.css,mosra/m.css