Using commands:
```
glib/gen-unicode-tables.pl -both 13.0.0 path/to/UCD
tests/gen-casefold-txt.py 13.0.0 path/to/UCD/CaseFolding.txt \
> tests/casefold.txt
tests/gen-casemap-txt.py 13.0.0 path/to/UCD/UnicodeData.txt \
path/to/UCD/SpecialCasing.txt > tests/casemap.txt
```
Using UCD release https://www.unicode.org/Public/zipped/13.0.0/UCD.zip
With some manual additions to `GUnicodeScript` for the 4 new scripts
added in 13.0, using the first assigned character in each block in
`glib/tests/unicode.c`.
Signed-off-by: Philip Withnall <withnall@endlessm.com>