chore(deps): update golang docker tag to v1.13 (#81)

Author: renovate-bot

system-test/Dockerfile.linux

@@ -1,4 +1,4 @@
-FROM golang:1.12-stretch as builder
+FROM golang:1.13-stretch as builder
 RUN apt-get update && apt-get install -y \
     git \
  && rm -rf /var/lib/apt/lists/*

system-test/Dockerfile.node10-alpine

@@ -1,4 +1,4 @@
-FROM golang:1.12-alpine as builder
+FROM golang:1.13-alpine as builder
 RUN apk add --no-cache git
 WORKDIR /root/
 RUN go get github.com/google/pprof

system-test/Dockerfile.node11-alpine

@@ -1,4 +1,4 @@
-FROM golang:1.12-alpine as builder
+FROM golang:1.13-alpine as builder
 RUN apk add --no-cache git
 WORKDIR /root/
 RUN go get github.com/google/pprof

system-test/Dockerfile.node12-alpine

@@ -1,4 +1,4 @@
-FROM golang:1.12-alpine as builder
+FROM golang:1.13-alpine as builder
 RUN apk add --no-cache git
 WORKDIR /root/
 RUN go get github.com/google/pprof

system-test/Dockerfile.node8-alpine

@@ -1,4 +1,4 @@
-FROM golang:1.12-alpine as builder
+FROM golang:1.13-alpine as builder
 RUN apk add --no-cache git
 WORKDIR /root/
 RUN go get github.com/google/pprof