Add unzip to required build tools

[iliaal]

When an extension declares download-url-method: ["pre-packaged-binary", ...], PIE calls setDistUrl(zip-url) so composer downloads and extracts the .so into the vendor dir. composer's archive downloader probes for /usr/bin/unzip first. When it isn't present, composer doesn't fall back to PHP's ZipArchive; it falls back to git-cloning the source. The prebuilt dist is silently discarded, the .so never lands in the vendor dir, and UnixBuild::prePackagedBinary trips ExtensionBinaryNotFound looking for it.

php:X.Y-cli Debian images don't ship /usr/bin/unzip, so this hits any pie install <pkg> on a minimal container when the extension publishes prebuilt binaries. Repro:

docker run --rm php:8.4-cli sh -c '
    apt-get update -qq
    apt-get install -y -qq curl git ca-certificates  # no unzip
    curl -sSL https://github.com/php/pie/releases/download/1.4.4/pie.phar \
        -o /usr/local/bin/pie && chmod +x /usr/local/bin/pie
    pie install --with-php-config=/usr/local/bin/php-config \
        --auto-install-build-tools iliaal/fastchart'

The patch adds unzip to CheckAllBuildTools::buildToolsFactory() alongside the existing tools. Package name is unzip on apt/apk/dnf/yum/brew. With --auto-install-build-tools, PIE installs it and the prebuilt-binary lane works.

Caught while releasing iliaal/fastchart 1.1.1.