Bump alpine from 3.17.2 to 3.17.3 (#35)

Dockerfile

@@ -1,4 +1,4 @@
-FROM docker.io/alpine:3.17.2
+FROM docker.io/alpine:3.17.3
 
 ARG OPENVPN_PACKAGE_VERSION=2.5.8-r0
 RUN apk add --no-cache openvpn=$OPENVPN_PACKAGE_VERSION