downgrade alpine to 3.20 (#461)

Author: nianyush

Earthfile

@@ -5,7 +5,7 @@ ARG TARGETARCH
 # Default image repositories used in the builds.
 ARG SPECTRO_PUB_REPO=us-docker.pkg.dev/palette-images
 ARG SPECTRO_THIRD_PARTY_IMAGE=us-east1-docker.pkg.dev/spectro-images/third-party/spectro-third-party:4.6
-ARG ALPINE_TAG=3.22
+ARG ALPINE_TAG=3.20
 ARG ALPINE_IMG=$SPECTRO_PUB_REPO/edge/canvos/alpine:$ALPINE_TAG
 FROM $ALPINE_IMG