Upgrade pest to 2.7.6 am: 977f5c28ca

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/pest/+/2949317

Change-Id: Ibcdc9f9c2ef9e99e07d9b7075eb0694b960e5aa3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>