Upgrade syn-mid to 0.6.0 am: 336bed4254 am: d8fdf40716 am: 28bc4652ae

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/syn-mid/+/2832419

Change-Id: I8fed778ab61523f16dd166456239848e34b132b1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>