Update checkout for tensorflow/swift-apis. (#28124)
https://github.com/tensorflow/swift-apis/commit/1aceb2d801ff8e0cc8eeb15f5c8957f2c9d2e1f7
`-DCOMPILING_TENSORFLOW_MODULE` has been renamed to
`-DCOMPILING_TENSORFLOW_STDLIB_MODULE` for clarity.
`STDLIB` emphasizes that the flag is relevant for building the Swift stdlib.
