fix(profiling): fix endpoint profiling for stack v2 (#10246)

Stack v1 implementation

https://github.com/DataDog/dd-trace-py/blob/9029186edf9d21e3ff375eb694e60d47f92c0f96/ddtrace/profiling/event.py#L107-L108

Wrong stack v2 implementation

https://github.com/DataDog/dd-trace-py/blob/f42fb50fcef8ef4dd00c168551a5e3b624c25878/ddtrace/internal/datadog/profiling/ddup/_ddup.pyx#L286-L287

Found this while working on #10230. Submitting this as a separate PR to
merge and backport this ASAP.


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ddtrace/internal/datadog/profiling/ddup/_ddup.pyx

@@ -284,10 +284,10 @@ cdef class SampleHandle:
             span_type_bytes = ensure_binary_or_empty(span._local_root.span_type)
             ddup_push_trace_type(self.ptr, string_view(<const char*>span_type_bytes, len(span_type_bytes)))
         if endpoint_collection_enabled:
-            root_service_bytes = ensure_binary_or_empty(span._local_root.service)
+            root_resource_bytes = ensure_binary_or_empty(span._local_root.resource)
             ddup_push_trace_resource_container(
                     self.ptr,
-                    string_view(<const char*>root_service_bytes, len(root_service_bytes))
+                    string_view(<const char*>root_resource_bytes, len(root_resource_bytes))
             )
 
     def push_monotonic_ns(self, monotonic_ns: int) -> None:

releasenotes/notes/profiling-fix-endpoint-v2-a6ca2ebbc9701fe5.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    profiling: Fixes endpoing profiling for stack v2, that is when
+    ``DD_PROFILING_STACK_V2_ENABLED`` set.
+