remove tvOS from template (#28706)

Summary:
According to the [0.62 blog post](https://reactnative.dev/blog/2020/03/26/version-0.62), Apple TV support has moved to react-native-tvos.
The template still contains info.plist for tvOS, so I've removed them for future releases.

## Changelog

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[General] [Removed] - Removed tvOS related files from the template
Pull Request resolved: #28706

Test Plan: run `react-native init TestTemplate` and remove tvOS related files and verified that iOS and Android runs on emulator.

Differential Revision: D21182211

Pulled By: hramos

fbshipit-source-id: 41d2e19e5158d7ec103a37c01a93cf511fc1e4c9