Use wpi::span instead of wpi::ArrayRef across all libraries (#3414)

- Remove ArrayRef.h
- Add SpanExtras.h for a couple of convenience functions

wpiutil/src/main/native/cpp/uv/Process.cpp

@@ -11,7 +11,7 @@
 namespace wpi::uv {
 
 std::shared_ptr<Process> Process::SpawnArray(Loop& loop, std::string_view file,
-                                             ArrayRef<Option> options) {
+                                             span<const Option> options) {
   // convert Option array to libuv structure
   uv_process_options_t coptions;