docker: update base image to Alpine 3.13.2

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 3.3.1
+
+OTHER:
+
+- update base of Docker image to Alpine 3.13.2 to fix security vulnerabilities
+
 ## 3.3.0 (January 18, 2021)
 
 OTHER:

docker/Dockerfile

@@ -1,8 +1,8 @@
-FROM alpine:3.13
+FROM alpine:3.13.2
 
 EXPOSE 5353 8080
 
-ARG DYNDNSD_VERSION=3.0.0
+ARG DYNDNSD_VERSION=3.3.0
 
 RUN apk --no-cache add openssl ca-certificates && \
     apk --no-cache add ruby ruby-etc ruby-io-console ruby-json ruby-webrick && \