Issues in doc on importing a distribution from a Docker container

[NotTheDr01ds]

Documentation Issue

Several issues in this doc:

1. The most serious is that the "Prerequisites" section says that Docker Desktop needs to be installed (good), but then Step 2 says that you need to run sudo service docker start (bad). If you have Docker Desktop installed, then that will result in the error start: unrecognized service. This is expected, since Docker Desktop does not install Docker Engine into the distribution itself, of course. Whoever wrote this (and captured the screenshot) was running Docker Engine rather than Docker Desktop.

2. Step 4 is unnecessary and can be greatly simplified.

3. There is no "cleanup" done for the resulting container, so it is left in an Exited state indefinitely (even after WSL and/or Docker restart).

4. Minor, but the alt text for the image in Importing CentOS example is "Example of the above commands running in WSL" when these steps were all in PowerShell.

Link to documentation page

https://learn.microsoft.com/en-us/windows/wsl/use-custom-distro#obtaining-a-tar-file-for-centos-example

Suggested Improvements

1. Recommended that Step 2 be removed completely, since Microsoft's recommended way of installing Docker is to use Docker Desktop (not Docker Engine).

2. Recommend modifying Step 3 to use docker run -t --name wsl_export centos bash ls /. Step 5's $dockerContainerID could then be replaced by wsl_export. Step 4 can then be removed completely.

3. Recommend a new final step to docker rm wsl_export

4. Update image alt/description to "Example of the above commands running in PowerShell"