Update deps and Alpine image

- Updated deps
- Updated Alpine images to 3.16
- Removed dumb-init, not needed anymore
- Some small shellcheck tweaks on the start/healthcheck scripts

docker/amd64/Dockerfile.buildx.alpine

@@ -81,7 +81,7 @@ RUN --mount=type=cache,target=/root/.cargo/git --mount=type=cache,target=/root/.
 ######################## RUNTIME IMAGE  ########################
 # Create a new stage with a minimal image
 # because we already have a binary built
-FROM alpine:3.15
+FROM alpine:3.16
 
 ENV ROCKET_PROFILE="release" \
     ROCKET_ADDRESS=0.0.0.0 \
@@ -96,7 +96,6 @@ RUN mkdir /data \
         openssl \
         tzdata \
         curl \
-        dumb-init \
         ca-certificates
 
 
@@ -115,10 +114,4 @@ COPY docker/start.sh /start.sh
 
 HEALTHCHECK --interval=60s --timeout=10s CMD ["/healthcheck.sh"]
 
-# Configures the startup!
-# We should be able to remove the dumb-init now with Rocket 0.5
-# But the balenalib images have some issues with there entry.sh
-# See: https://github.com/balena-io-library/base-images/issues/735
-# Lets keep using dumb-init for now, since that is working fine.
-ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 CMD ["/start.sh"]