Upgrade rust/crates/thiserror-impl to 1.0.21 am: 545fd6fbe4 am: edb47677a3

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/thiserror-impl/+/1474959

Change-Id: I5c9ad9d9b66c47ee4dbcad1f111ba47b14aebffa