Support new compound operators `is not` and `not in`

[zaneduffield]

Delphi 13 added new compound operators to negate the existing is and not operators (documentation).

pasfmt should be updated to force no line breaks between such keywords.

For example, in pasfmt 0.6.0 (with wrap_column=30) you would get

A :=
    aaaaaaaaaaaa not
        in bbbbbbbbbbbbb;

but the best formatting would be to prevent the break between not and in to get

A :=
    aaaaaaaaaaaa not in
        bbbbbbbbbbbbb;