update-build-files: bump buildifier version

[AlexTereshenkov]

Bumping the buildifier version to the latest one available: https://github.com/bazelbuild/buildtools/releases/tag/v7.1.2.

Running this tiny script to produce the versions metadata after downloading the relevant files from the GitHub page:

declare -A platform_mapping
platform_mapping["darwin-arm64"]="macos_arm64"
platform_mapping["darwin-amd64"]="macos_x86_64"
platform_mapping["linux-arm64"]="linux_arm64"
platform_mapping["linux-amd64"]="linux_x86_64"

for f in $(ls buildifier-*); do
    platform=$(echo $f | awk -F- '{print $2"-"$3}') 
    echo "7.1.2|${platform_mapping["$platform"]}|$(shasum -a 256 $f|awk '{print $1}')|$(wc -c $f|awk '{print $1}')"; 
done

[huonw]

Looks good.

I'm imagining you may've been thinking of this logic with the no-release-notes required and replacement?

1. Before update-build-files: add support for Buildifier formatter #21208, no-one could be using buildifier
2. This PR is landing in the same release
3. Therefore, it's not worth doing either of:
   1. preserving support for version 5.1.0 by just adding 7.1.2 as a new known version, rather than replacing the existing one (since no-one could be actually invoking version 5.1.0)
   2. calling this out in the release notes since no-one will notice the "change" from 5.1.0 to 7.1.2

If so, sound good!

[AlexTereshenkov]

Yes, that's exactly what I thought. I don't think we need to support more than one version since the previous one wasn't usable. The upcoming upgrades will of course respect the most recently added one.