[DOC] Fix OTLP documentation: Default endpoint is wrong for OTLP/HTTP #9258

Job	Run time
Bazel noexcept	11m 39s
Bazel asan config	14m 33s
Bazel nortti	12m 6s
Bazel	13m 29s
Bazel with async export	13m 5s
Bazel valgrind	14m 56s
CMake test (with abseil)	4m 29s
Bazel with external abseil	12m 24s
CMake clang 15 (maintainer mode, abiv2)	14m 27s
CMake clang 15 (maintainer mode, async)	14m 47s
CMake clang 15 (maintainer mode, sync)	14m 2s
CMake do not install test (with otlp-exporter)	13m 50s
CMake gcc 13 (maintainer mode, async)	6m 42s
CMake gcc 13 (maintainer mode, sync)	7m 23s
CMake install test (with abseil)	4m 19s
CMake test (with modern protobuf,grpc and abseil)	17m 59s
CMake msvc (maintainer mode)	7m 35s
CMake msvc (maintainer mode) with C++20	8m 35s
CMake test (with opentracing-shim)	4m 46s
CMake test (build shared libraries with otlp-exporter and static gRPC)	13m 47s
CMake test (with otlp-exporter)	14m 10s
CMake test (without otlp-exporter)	5m 3s
CMake C++14 test(GCC)	4m 18s
CMake C++17 test(GCC)	5m 5s
CMake C++20 test(Clang with libc++)	10m 14s
CMake C++20 test(GCC)	8m 48s
CMake C++23 test(GCC)	8m 42s
CMake C++23 test(Clang with libc++)	9m 31s
CMake test (without otlp-exporter and with async export)	4m 43s
Plugin -> CMake	1m 5s
Bazel on MacOS	26m 4s
Bazel tsan config	12m 34s
Benchmark	8m 4s
Copyright	4s
CMake -> exporter proto	14m 52s
Format	16s
CMake (With async export) -> exporter proto	14m 39s
CMake -> exporter proto (Build as DLL)	38m 6s
Code coverage	11m 44s
DocFX check	1m 55s
markdown-lint	12s
misspell	4s
Bazel Windows	21m 34s
Plugin -> CMake Windows	8m 50s
	7h 35m 30s

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