Added INTRO-emscripten.md #3646

Job	Run time
Create test plan	4s
level1 / Haiku	1m 56s
level2 / Sony PlayStation Vita (GLES w/ pib)	3m 21s
level2 / Sony PlayStation 2	5m 11s
level2 / Android (CMake, lean)	2m 56s
level2 / Windows (msys2, mingw32)	9m 12s
level2 / Windows (MSVC, x64)	7m 8s
level2 / GDK (MSVC, x64)	1m 53s
level2 / Ubuntu 20.04 (Intel oneAPI)	7m 42s
level2 / Emscripten	9m 23s
level2 / NetBSD	2m 55s
level2 / Windows (msys2, ucrt64)	8m 26s
level2 / Nintendo 3DS	2m 9s
level2 / PowerPC	1m 47s
level2 / Windows (msys2, clang32)	7m 25s
level2 / Windows (MSVC, x86)	6m 1s
level2 / Windows (MSVC, clang-cl x86)	5m 42s
level2 / MacOS (GNU prefix)	3m 30s
level2 / Android (Gradle)	2m 33s
level2 / Steam Linux Runtime (Sniper)	3m 6s
level2 / LoongArch64	4m 7s
level2 / Windows (MSVC, clang-cl x64)	6m 8s
level2 / tvOS (CMake & xcode)	2m 34s
level2 / Windows (msys2, clang64)	5m 58s
level2 / RISC OS	1m 22s
level2 / Windows (msys2, mingw64)	8m 17s
level2 / Sony PlayStation Vita (GLES w/ PVR_PSP2)	3m 30s
level2 / Android (CMake)	4m 8s
level2 / Android (Android.mk)	1m 9s
level2 / FreeBSD	2m 44s
level2 / PowerPC64	1m 48s
level2 / Ubuntu 20.04	6m 15s
level2 / MacOS (Framework) (x64)	9m 15s
level2 / Ubuntu 20.04 (Intel Compiler)	5m 31s
level2 / Windows (MSVC, ARM64)	4m 26s
level2 / Windows (MSVC, ARM)	4m 9s
level2 / Sony PlayStation Portable	3m 45s
level2 / MacOS (Framework) (arm64)	2m 31s
level2 / Ubuntu 22.04	4m 20s
level2 / iOS (CMake & xcode)	2m 16s
	2h 56m 33s

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