[0.79] Remove fixtures from `@react-native/codegen` published files and drop outdated Babel transforms

[kitten]

Target Branch(es)

0.79

Link to commit or PR to be picked

facebook/react-native@b52f0d8

Description

This is highly optional, but filing this to complement #831, since if that one is picked, this one would be a straightforward addition, and in line with the other cleanups I've submitted that did make it into 0.79.

This request is definitely more of a nice to have than the other, but it does shrink the tarball size of the published package, which helps with install/download speed marginally (which admittedly is a drop in the ocean, but every little bit helps)

[react-native-bot]

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   • A core component is behaving differently between version 0.X and 0.X-1
   • The TurboModule.getEnforcing function is throwing an assertion error which is not expected.
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[cortinico]

Closing as discussed in person. This can land in 0.80