Only define ARGs at the top

Dockerfile

@@ -11,10 +11,8 @@ ARG GID=991
 
 
 ### Build Hardened Malloc
-ARG ALPINE_VERSION
 FROM docker.io/alpine:${ALPINE_VERSION} as build-malloc
 
-ARG HARDENED_MALLOC_VERSION
 ARG CONFIG_NATIVE=false
 
 COPY thestinger.gpg /tmp/
@@ -26,13 +24,8 @@ RUN apk --no-cache add build-base git gnupg && cd /tmp \
 
 
 ### Build Mastodon
-ARG ALPINE_VERSION
-
 FROM docker.io/alpine:${ALPINE_VERSION} as mastodon-build
 
-ARG MASTODON_VERSION
-ARG MASTODON_REPOSITORY
-
 # Install build dependencies
 RUN apk --no-cache add -t build-dependencies \
     build-base \
@@ -74,13 +67,8 @@ RUN yarn install --pure-lockfile --ignore-engines \
 
 
 ### Mastodon runtime
-ARG ALPINE_VERSION
-
 FROM docker.io/alpine:${ALPINE_VERSION} as mastodon
 
-ARG UID
-ARG GID
-
 ENV RUN_DB_MIGRATIONS=true \
     SIDEKIQ_WORKERS=5 \
     BIND=0.0.0.0 \