Update alpine Docker tag to v3.18.2

Author: renovate[bot]

deployment/Dockerfile

@@ -27,7 +27,7 @@ COPY pkg ./pkg
 RUN go install .
 
 # production image ############################################
-FROM alpine:3.15.4@sha256:4edbd2beb5f78b1014028f4fbb99f3237d9561100b6881aabbf5acce2c4f9454 AS prod
+FROM alpine:3.18.2@sha256:5246eec74dffc9a5f6608c4e7c81bd33455ecc64f558bf49eb334c4f05e47eee AS prod
 RUN apk add --no-cache ca-certificates
 
 # tracing config