community/cargo-watch: bump getrandom crate to fix open64
Fixes error found during 3.19 rebuild: https://build.alpinelinux.org/buildlogs/build-3-19-x86_64/community/cargo-watch/cargo-watch-8.4.0-r2.log
Fixes error found during 3.19 rebuild: https://build.alpinelinux.org/buildlogs/build-3-19-x86_64/community/cargo-watch/cargo-watch-8.4.0-r2.log