Update Go version to 1.15

Author: Dean-Coakley

.travis.yml

@@ -3,7 +3,7 @@ sudo: required
 services:
 - docker
 go:
-- "1.14"
+- "1.15"
 script:
 - echo "Nginx ASG sync - commit:${TRAVIS_COMMIT}"
 - make BUILD_IN_CONTAINER=0 all

Makefile

@@ -1,5 +1,5 @@
 GO_DOCKER_RUN = docker run --rm -v $(shell pwd):/go/src/github.com/nginxinc/nginx-asg-sync -v $(shell pwd)/build_output:/build_output -w /go/src/github.com/nginxinc/nginx-asg-sync/cmd/sync
-GOLANG_CONTAINER = golang:1.14
+GOLANG_CONTAINER = golang:1.15
 BUILD_IN_CONTAINER = 1
 GOFLAGS ?= -mod=vendor
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/nginxinc/nginx-asg-sync
 
-go 1.14
+go 1.15
 
 require (
 	github.com/Azure/azure-sdk-for-go v42.3.0+incompatible