CMake: Rename serenity_* helper functions/macros to ladybird_*

Author: https://github.com/ayeteadoe
Commit: 25f5936dee
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5249
Reviewed-by: https://github.com/gmta ✅

Libraries/LibRegex/CMakeLists.txt

@@ -10,5 +10,5 @@ if(SERENITYOS)
     list(APPEND SOURCES C/Regex.cpp)
 endif()
 
-serenity_lib(LibRegex regex EXPLICIT_SYMBOL_EXPORT)
+ladybird_lib(LibRegex regex EXPLICIT_SYMBOL_EXPORT)
 target_link_libraries(LibRegex PRIVATE LibUnicode)