[css-writing-modes] editorial tweaking of text link (Appendix C)

Koji, Elika,

1)
In
5. Introduction to Vertical Text Layout
https://drafts.csswg.org/css-writing-modes-3/#intro-text-layout

"
(...) See Appendix C for a categorization (...)
"

but there is no Appendix C. It should be Appendix A.

2)
In
Appendix A: Vertical Scripts in Unicode
https://drafts.csswg.org/css-writing-modes-3/#script-orientations

"
(...) as belonging ot a (...)
"

It should be
"
(...) as belonging to a (...)
"

Gérard