adds compression to compiled binary to make it smaller.

build-certificate-monitor.jenkins

@@ -13,12 +13,13 @@ sonar.go.coverage.reportPaths=cover.out
 """
 def dockerfile = """
 FROM golang:alpine AS BUILDER
-RUN apk --no-cache add git
+RUN apk --no-cache add git upx
 WORKDIR /go/src/app
 COPY . .
 RUN go get -d -v ./... && \\
   go install -v ./... && \\
-  go build -ldflags="-s -w" -o app ./
+  go build -ldflags="-s -w" -o app ./ && \\
+  upx --brute app
 
 FROM alpine:latest
 RUN apk add --no-cache ca-certificates && \\