Changes required for .NET 11 RC1

- [x] Switch to non-preview tagging pattern for .NET 11 - https://github.com/dotnet/dotnet-docker/pull/7327
- Remove preview suffix from tags in `manifest.json` and/or `manifest.versions.json`
- Move new version tags out of preview sub-tables in [MCR tags metadata templates](https://github.com/dotnet/dotnet-docker/tree/main/eng/mcr-tags-metadata-templates)
- In [readme templates](https://github.com/dotnet/dotnet-docker/blob/main/eng/readme-templates/FeaturedTags.md):
- Switch Featured Tags from "(Preview)" to "(Release Candidate)" in `nightly` branch
- Add new .NET Version to Featured Tags as "(Release Candidate)" in `main` branch
- [ ] https://github.com/dotnet/dotnet-docker/pull/7352
- [ ] Consider creating new samples for new features
- [x] Update documentation to reference the new .NET version
- [ ] Update IIS sample URL to preview version of `dotnet-hosting-win.exe` (`/dotnet//preview/`): .
- [ ] Review supported OS versions for new .NET version before release. Follow the [supported operating systems documentation](https://github.com/dotnet/dotnet-docker/blob/main/documentation/supported-platforms.md#operating-systems).