Log Message:
libical: update to 3.0.19.

Version 3.0.19 (23 December 2024):
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 * Fix for changes to the libicu 75 API
 * Add vcpkg manifest-mode support
 * Improved berkeley-db discovery on Mac with homebrew
 * Improved libicu discrovery on Mac with homebrew
 * Properly set DYLD_LIBRARY_PATH on Mac for libical-ical tests
 * Resolved known limitation: Negative values are now also supported for \ 
`BYMONTHDAY` and `BYYEARDAY`.
 * Add support for RDATE;VALUE=PERIOD
 * Fix time conversion to time_t for times before epoch
 * Allow `icalcomponent_foreach_recurrence` to receive `DATE`-only `start` and \ 
`end` params.
 * Fix the calculation of an event's duration if `DTSTART` is a `DATE`-only value.
 * Fix `icaltime_span_new()` - ignore the case where DTEND is unset and require \ 
it to be set by the caller instead.
 * Various fixes for fuzzer issues