[EXPORTER] Fix forward protocol encoding for ETW exporter #9021

Job	Run time
Bazel nortti	13m 1s
Bazel noexcept	12m 0s
Bazel asan config	16m 8s
Bazel on MacOS	15m 16s
Bazel	12m 25s
Bazel with async export	13m 1s
Bazel tsan config	13m 44s
Bazel valgrind	14m 28s
Bazel with external abseil	13m 53s
Benchmark	8m 7s
CMake test (with abseil)	5m 31s
CMake clang 14 (maintainer mode, abiv2)	14m 24s
CMake clang 14 (maintainer mode, async)	13m 52s
CMake clang 14 (maintainer mode, sync)	14m 21s
CMake do not install test (with otlp-exporter)	15m 29s
CMake gcc 12 (maintainer mode, async)	8m 29s
CMake gcc 12 (maintainer mode, sync)	8m 7s
CMake install test (with abseil)	4m 53s
CMake test (with modern protobuf,grpc and abseil)	20m 4s
CMake msvc (maintainer mode)	7m 36s
CMake msvc (maintainer mode) with C++20	9m 35s
CMake test (with opentracing-shim)	4m 12s
CMake test (build shared libraries with otlp-exporter and static gRPC)	13m 49s
CMake test (with otlp-exporter)	14m 30s
CMake test (without otlp-exporter)	5m 1s
CMake C++14 test(GCC)	5m 37s
CMake C++17 test(GCC)	5m 7s
CMake C++20 test(Clang with libc++)	9m 23s
CMake C++20 test(GCC)	10m 26s
CMake test (without otlp-exporter and with async export)	5m 2s
Code coverage	12m 30s
Copyright	6s
DocFX check	58s
Format	13s
markdown-lint	7s
misspell	7s
Plugin -> CMake	59s
CMake -> exporter proto	12m 33s
Bazel Windows	22m 36s
Plugin -> CMake Windows	6m 18s
CMake -> exporter proto (Build as DLL)	12m 28s
CMake (With async export) -> exporter proto	12m 3s
	6h 48m 29s

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