Changes the default fetcher in the Rust Platform to be the newer
`fetchCargoTarball`, and changes every application using the current default to
instead opt out.
This commit does not change any hashes or cause any rebuilds. Once integrated,
we will start deleting the opt-outs and recomputing hashes.
See #79975 for details.
The previous hash was generated on aarch64. Due to https://github.com/NixOS/nixpkgs/issues/60668 the hash is different on different platforms. I am updating to use the x86_64-linux hash to fix building on hydra.
wasm-pack is a workflow tool maintained by the Rust and WebAssembly
Working Group to make working with Rust-generated WebAssembly packages
easier to work with.
