[policy, no patch] Drop support for Windows in production in Drupal 11

Problem/Motivation

Following on from 🌱 [policy, no patch] Drop support for Windows in production Needs review . It is recommended to read that issue and the comments.

Windows has added full support for running Linux distros within Windows. There's also docker (and ddev which runs on docker) that make it easy to set up development environments in using containers. Actual manual configuration of apache for local development is very optional these days.

Additionally, it's also hard to find reviewers for issues with windows issues - for example filesystem bugs. Also, we have no way to add automated testing for Windows environments.

Note that there's an issue to move example nginx configuration into core, but that would only be an example ✨ Provide documentation/default server block for Nginx server. Needs work , not 'live' config, it's also not anywhere near RTBC.

Proposed resolution

Stop supporting running Drupal directly on Windows on production. We would still accept bug reports for Windows on development environments. One example is something like not using DIRECTORY_SEPARATOR correctly.

Sites wanting to use Windows servers in production would need to run Drupal on Linux on Windows, which should not result in additional surface area for security reports against Drupal, since as far as Drupal's concerned it would still be running on Linux.

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet