Update Windows docs for WSL2 (#2816)

Author: kiview

docs/supported_docker_environment/windows.md

@@ -4,26 +4,31 @@
 * [Docker for Windows](https://docs.docker.com/docker-for-windows/) needs to be installed
   * Docker version 17.06 is confirmed to work on Windows 10 with Hyper-V.
   * Testcontainers supports communication with Docker on Docker for Windows using named pipes.
+  * WSL2 backend is supported starting with Windows 10 2004. (**Beta**)
 
 ## Limitations
 The following features are not available or do not work correctly so make sure you do not use them or use them with 
 caution. The list may not be complete.
 
-### Testing
-
-Testcontainers is not regularly tested on Windows, so please consider it to be at an beta level of readiness.
-
-If you wish to use Testcontainers on Windows, please confirm that it works correctly for you before investing significant
-effort.
-
 ### MySQL containers
 * MySQL server prevents custom configuration file (ini-script) from being loaded due to security measures ([link to feature description](../modules/databases/index.md#using-an-init-script-from-a-file))
 
 ### Windows Container on Windows (WCOW)
 
 * WCOW is currently not supported, since Testcontainers uses auxiliary Linux containers for certain tasks and Docker for Windows does not support hybrid engine mode at the time of writing.
 
-## Windows Subsystem for Linux
+## WSL2 backend
+
+Using Docker for Windows with WSL2 backend should work out of the box.
+
+However, there is an [existing issue](https://github.com/microsoft/WSL/issues/4694) in WSL/WSL2 that effects certain older Docker images. 
+The currently proposed workaround is to enable vsyscall emulation in the WSL2 kernel:
+```
+[wsl2]
+kernelCommandLine = vsyscall=emulate
+```
+
+## Windows Subsystem for Linux (WSL)
 
 Testcontainers supports communicating with Docker for Windows within the Windows Subsystem for Linux *([**WSL**](https://docs.microsoft.com/en-us/windows/wsl/about))*.
 The following additional configurations steps are required: