Update to syn-2 am: 2f79acbc52 am: 82dd91491f am: 99144e4d5b am: 09d1541e36 am: 01f1de6f7d

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/pin-project-internal/+/2523138

Change-Id: I5f02bc8303f709e0d1a77c56a60cd34615876fd2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>