Remove Windows occurrences from site "Create a Plugin"

[GitToTheHub]

The windows platform is not supported anymore

Platforms affected

Motivation and Context

Description

Testing

Checklist

• I've run the tests to see all new and existing tests pass
• I added automated test coverage as appropriate for this change
• Commit is prefixed with (platform) if this change only applies to one platform (e.g. (android))
• If this Pull Request resolves an issue, I linked to the issue in the text above (and used the correct keyword to close issues using keywords)
• I've updated the documentation if necessary

[breautek]

I think these improvements are good, especially since that windows link is actually a 404 as well.

The only thing is, the changes are made to dev which means they will apply on our next version snapshot, which is good but I think these changes also warrants being updated on our 12.x version of the docs as well. This can be done by mirroring the changeset on https://github.com/apache/cordova-docs/blob/master/www/docs/en/12.x/guide/hybrid/plugins/index.md file. This way when the PR is merged the change will be live on the current docs as well.

Would you like to do this?

[GitToTheHub]

No problem, I can do that 🙂

[GitToTheHub]

@breautek I reflected the changes to the 12.x docs and squashed the changes on the dev-docs to one commit

[breautek]

Awesome thanks!