Replace gzip with pigz for faster builds (#4411)

Signed-off-by: dereknola <derek.nola@suse.com>

Dockerfile.dapper

@@ -11,7 +11,7 @@ ENV no_proxy=$no_proxy
 RUN apk -U --no-cache add bash git gcc musl-dev docker vim less file curl wget ca-certificates jq linux-headers \
     zlib-dev tar zip squashfs-tools npm coreutils python3 openssl-dev libffi-dev libseccomp libseccomp-dev \
     libseccomp-static make libuv-static sqlite-dev sqlite-static libselinux libselinux-dev zlib-dev zlib-static \
-    zstd gzip alpine-sdk binutils-gold btrfs-progs-dev btrfs-progs-static
+    zstd pigz alpine-sdk binutils-gold btrfs-progs-dev btrfs-progs-static
 RUN if [ "$(go env GOARCH)" = "arm64" ]; then                                                               \
     wget https://github.com/aquasecurity/trivy/releases/download/v0.16.0/trivy_0.16.0_Linux-ARM64.tar.gz && \
     tar -zxvf trivy_0.16.0_Linux-ARM64.tar.gz                                                            && \

scripts/package-airgap

@@ -10,7 +10,7 @@ images=$(cat "${airgap_image_file}")
 xargs -n1 docker pull <<< "${images}"
 docker save ${images} -o dist/artifacts/k3s-airgap-images-${ARCH}.tar
 zstd --no-progress -T0 -16 -f --long=25 dist/artifacts/k3s-airgap-images-${ARCH}.tar -o dist/artifacts/k3s-airgap-images-${ARCH}.tar.zst
-gzip -v -c dist/artifacts/k3s-airgap-images-${ARCH}.tar > dist/artifacts/k3s-airgap-images-${ARCH}.tar.gz
+pigz -v -c dist/artifacts/k3s-airgap-images-${ARCH}.tar > dist/artifacts/k3s-airgap-images-${ARCH}.tar.gz
 if [ ${ARCH} = amd64 ]; then
   cp "${airgap_image_file}" dist/artifacts/k3s-images.txt
 fi