Upgrade pest_meta to 2.7.6 am: a8409b3d22

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/pest_meta/+/2949315

Change-Id: Ia24c6f043c95698b50e28223d445b5405c4a83a5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>