[EXPORTER] Prometheus: Sanitize labels according to spec #8537

Job	Run time
CMake test (with abseil)	8m 46s
CMake clang 14 (maintainer mode, async)	17m 58s
CMake gcc 12 (maintainer mode, async)	10m 43s
CMake clang 14 (maintainer mode, sync)	17m 30s
CMake gcc 12 (maintainer mode, C++11, async)	15m 37s
CMake gcc 12 (maintainer mode, sync)	12m 3s
CMake msvc (maintainer mode)	12m 1s
CMake test (with opentracing-shim)	8m 0s
CMake test (without otlp-exporter)	8m 18s
CMake test (without otlp-exporter and with async export)	6m 21s
CMake do not install test (with otlp-exporter)	20m 35s
CMake gcc 4.8 (without otlp exporter)	5m 37s
CMake gcc 4.8 (with otlp exporter)	15m 17s
CMake test (with modern protobuf,grpc and abseil)	28m 43s
CMake test (with otlp-exporter)	28m 52s
CMake C++20 test(Clang with libc++)	14m 6s
CMake C++20 test(GCC)	13m 18s
Bazel noexcept	23m 50s
Bazel nortti	30m 5s
Bazel	19m 29s
Bazel with async export	19m 6s
Bazel valgrind	24m 48s
Bazel with external abseil	24m 36s
CMake test (build shared libraries with otlp-exporter and static gRPC)	26m 23s
CMake install test (with abseil)	9m 12s
Plugin -> CMake	1m 37s
Bazel asan config	13m 7s
Bazel on MacOS	25m 59s
Benchmark	16m 14s
Bazel tsan config	21m 2s
Copyright	8s
Format	17s
CMake -> exporter proto	24m 55s
CMake (With async export) -> exporter proto	23m 1s
CMake -> exporter proto (Build as DLL)	17m 2s
Code coverage	14m 34s
DocFX check	1m 13s
markdown-lint	6s
misspell	8s
Bazel Windows	47m 9s
Plugin -> CMake Windows	13m 37s
	10h 41m 23s

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