The `checkType` attribute does not apply after #113193,
and since we're changing tests anyway, let's run them
in the release mode to avoid the need for `checkType`.
This fixes the otherwise broken build.
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.
