Merge branch 'renovate/alpine-3.x' into 'main'

Update alpine Docker tag to v3.18.0

See merge request !29

Dockerfile

 # https://docs.docker.com/language/golang/build-images/#multi-stage-builds
 # https://hub.docker.com/_/golang/tags
-FROM golang:1.20.4-alpine3.17 AS build
+FROM  registry.hub.docker.com/library/golang:1.20.4-alpine3.18 AS build
 
 WORKDIR /app
 
@@ -13,11 +13,11 @@ RUN go mod download \
   && go build -v ./cmd/transmission-exporter
 
 # 2. stage
-FROM alpine:3.17.3
+FROM alpine:3.18.0
 COPY --from=build /app/transmission-exporter /usr/bin/transmission-exporter
 # COPY --chmod=755 .. requires Buildkit
 RUN chmod 755 /usr/bin/transmission-exporter \
-  && apk add --no-cache ca-certificates=20220614-r4
+  && apk add --no-cache ca-certificates=20230506-r0
 
 EXPOSE 19091