deps: update ICU to 73.1 final
- followon to #45068
- https://icu.unicode.org/download/73
- https://cldr.unicode.org/index/downloads/cldr-43
ICU 73 updates to CLDR 43 locale data with various additions and corrections. ICU 73 improves Japanese and Korean short-text line breaking, reduces C++ memory use in date formatting, and promotes the Java person name formatter from tech preview to draft. ICU 73 updates to the time zone data version 2023a (2023-mar) [same as 2023c]. Note that pre-1970 data for a number of time zones has been removed, as has been the case in the upstream tzdata release since 2021b.