Use `BLI_strncpy_utf8` & `BLI_snprintf_utf8` for fixed size buffers in
DNA and screen data structures such as panels, menus & operators.
This could be considered a fix as copying a UTF8 string into a smaller
buffer without proper truncation can create an invalid UTF8 sequence.
However identifying which of these users are likely to run into would
be time consuming and not especially useful.
649b89781e