fix(profiling): propagates runtime_id to libdatadog exporter (#9987)

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ddtrace/internal/datadog/profiling/dd_wrapper/src/uploader_builder.cpp

@@ -116,6 +116,7 @@ Datadog::UploaderBuilder::build()
         { ExportTagKey::version, version },
         { ExportTagKey::language, language },
         { ExportTagKey::runtime, runtime },
+        { ExportTagKey::runtime_id, runtime_id },
         { ExportTagKey::runtime_version, runtime_version },
         { ExportTagKey::profiler_version, profiler_version },
     };

releasenotes/notes/profiling-stack-v2-runtime-7a4700f8571deddc.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    profiling: propagates ``runtime_id`` tag to libdatadog exporter. It is
+    a unique string identifier for the profiled process. For example, Thread
+    Timeline visualization uses it to distinguish different processes.