Update Dockerfile

- Update to latest alpine release
- Update to latest submark release - Fixes #1
- Tag fixed submark version

Dockerfile

@@ -1,9 +1,9 @@
-FROM alpine:3.9 as base
+FROM alpine:3.16 as base
 
 RUN apk add --no-cache jq curl
 
 SHELL ["/bin/ash", "-o", "pipefail", "-c"]
-RUN curl -s https://api.github.com/repos/dahlia/submark/releases/latest |  jq -r '.assets[] | select(.browser_download_url | contains("linux-x86_64"))  | .browser_download_url' | xargs curl -o /usr/local/bin/submark -sSL &&  chmod +x /usr/local/bin/submark
+RUN curl -s https://api.github.com/repos/dahlia/submark/releases/tags/0.3.1 |  jq -r '.assets[] | select(.browser_download_url | contains("linux-x86_64"))  | .browser_download_url' | xargs curl -o /usr/local/bin/submark -sSL &&  chmod +x /usr/local/bin/submark
 
 COPY entrypoint.sh /entrypoint.sh