[opentracing-shim] Add check for sampled context (#2390) #1501

Job	Run time
Bazel asan config	10m 45s
Bazel noexcept	9m 12s
Bazel nortti	7m 53s
Bazel on MacOS	7m 39s
Bazel	7m 41s
Bazel with async export	20m 6s
Bazel tsan config	7m 40s
Bazel valgrind	10m 3s
Bazel with external abseil	19m 38s
Benchmark	3m 17s
CMake test (with abseil)	6m 44s
CMake clang 14 (maintainer mode, abiv2)	17m 31s
CMake clang 14 (maintainer mode, async)	20m 38s
CMake clang 14 (maintainer mode, sync)	18m 51s
CMake do not install test (with otlp-exporter)	21m 21s
CMake gcc 12 (maintainer mode, async)	11m 28s
CMake gcc 12 (maintainer mode, sync)	13m 11s
CMake install test (with abseil)	7m 23s
CMake msvc (maintainer mode)	10m 59s
CMake test (with modern protobuf,grpc and abseil)	31m 3s
CMake test (with opentracing-shim)	7m 8s
CMake test (build shared libraries with otlp-exporter and static gRPC)	20m 21s
CMake test (with otlp-exporter)	22m 2s
CMake test (without otlp-exporter)	8m 14s
CMake C++14 test(GCC)	5m 51s
CMake C++17 test(GCC)	9m 23s
CMake C++20 test(Clang with libc++)	12m 12s
CMake C++20 test(GCC)	16m 29s
CMake test (without otlp-exporter and with async export)	7m 8s
Code coverage	16m 53s
Copyright	6s
DocFX check	38s
markdown-lint	14s
Format	19s
misspell	7s
Plugin -> CMake	1m 35s
Bazel Windows	50m 9s
CMake -> exporter proto	22m 29s
Plugin -> CMake Windows	10m 24s
CMake (With async export) -> exporter proto	21m 44s
CMake -> exporter proto (Build as DLL)	18m 47s
	8h 35m 16s

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