[doc] Fix typo: Asynchronouse -> Asynchronous in meter.h #9371

Job	Run time
Bazel nortti	12m 33s
Bazel on MacOS	20m 45s
Bazel asan config	15m 17s
Bazel noexcept	11m 45s
Bazel	12m 32s
Bazel with async export	13m 8s
Bazel tsan config	13m 10s
Bazel valgrind	13m 59s
Bazel with external abseil	13m 17s
Benchmark	8m 23s
CMake test (with abseil)	4m 36s
CMake clang 15 (maintainer mode, abiv2)	13m 50s
CMake clang 15 (maintainer mode, async)	14m 17s
CMake clang 15 (maintainer mode, sync)	13m 59s
CMake do not install test (with otlp-exporter)	14m 39s
CMake gcc 13 (maintainer mode, async)	7m 11s
CMake gcc 13 (maintainer mode, sync)	8m 57s
CMake install test (with abseil)	4m 29s
CMake test (with modern protobuf,grpc and abseil)	20m 49s
CMake msvc (maintainer mode)	7m 10s
CMake msvc (maintainer mode) with C++20	8m 3s
CMake test (with opentracing-shim)	4m 34s
CMake test (build shared libraries with otlp-exporter and static gRPC)	13m 53s
CMake test (with otlp-exporter)	14m 43s
CMake test (without otlp-exporter)	4m 48s
CMake C++14 test(GCC)	4m 23s
CMake C++17 test(GCC)	4m 50s
CMake C++20 test(Clang with libc++)	9m 37s
CMake C++20 test(GCC)	8m 37s
CMake C++23 test(Clang with libc++)	9m 59s
CMake C++23 test(GCC)	9m 2s
CMake test (without otlp-exporter and with async export)	4m 32s
Code coverage	11m 49s
Copyright	6s
DocFX check	31s
Format	16s
markdown-lint	6s
misspell	4s
Plugin -> CMake	1m 21s
CMake -> exporter proto	11m 54s
Bazel Windows	20m 25s
Plugin -> CMake Windows	6m 26s
CMake (With async export) -> exporter proto	11m 52s
CMake -> exporter proto (Build as DLL)	26m 19s
	7h 12m 56s

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