corrects syntax

Jenkinsfile

@@ -24,7 +24,13 @@ spec:
     image: ${repository}/dockerhub/library/golang:latest
     tty: true
     command:
-    - /bin/cat
+    - /bin/sh
+  - name: alpine
+    image: ${repository}/library/alpine:latest
+    imagePullPolicy: Always
+    tty: true
+    command:
+    - /bin/sh
 """) {
     node (label) {
         def workspace = pwd()
@@ -112,7 +118,7 @@ RUN apk add --no-cache git upx && \\
     go get -d -v ./... && \\
     go install -v ./... && \\
     GOOG=linux GOARCH=amd64 CGO_ENABLED=0 go build -v -ldflags="-s -w" -tags timetzdata -o app ./cmd/tpapi && \\
-    upx --lzma --ultra-brute app
+    upx --lzma app
 
 FROM scratch