Copy supported platforms from README onto https://google.github.io/googletest/platforms.html

PiperOrigin-RevId: 537016664
Change-Id: Ie62891a1061465a009b90feba0ccb91d85591160

docs/platforms.md

@@ -1,35 +1,8 @@
 # Supported Platforms
 
-GoogleTest requires a codebase and compiler compliant with the C++11 standard or
+GoogleTest follows Google's
-newer.
+[Foundational C++ Support Policy](https://opensource.google/documentation/policies/cplusplus-support).
-
+See
-The GoogleTest code is officially supported on the following platforms.
+[this table](https://github.com/google/oss-policies-info/blob/main/foundational-cxx-support-matrix.md)
-Operating systems or tools not listed below are community-supported. For
+for a list of currently supported versions compilers, platforms, and build
-community-supported platforms, patches that do not complicate the code may be
+tools.
-considered.
-
-If you notice any problems on your platform, please file an issue on the
-[GoogleTest GitHub Issue Tracker](https://github.com/google/googletest/issues).
-Pull requests containing fixes are welcome!
-
-### Operating systems
-
-*   Linux
-*   macOS
-*   Windows
-
-### Compilers
-
-*   gcc 5.0+
-*   clang 5.0+
-*   MSVC 2015+
-
-**macOS users:** Xcode 9.3+ provides clang 5.0+.
-
-### Build systems
-
-*   [Bazel](https://bazel.build/)
-*   [CMake](https://cmake.org/)
-
-Bazel is the build system used by the team internally and in tests. CMake is
-supported on a best-effort basis and by the community.