variants:
  experimental:
    CONFIG: experimental
    GO_VERSION: 1.13.5
    K8S_RELEASE: stable
    BAZEL_VERSION: 0.28.1
    UPGRADE_DOCKER: 'true'
  master:
    CONFIG: master
    GO_VERSION: 1.13.5
    K8S_RELEASE: stable
    BAZEL_VERSION: 0.23.2
  '1.18':
    CONFIG: '1.18'
    GO_VERSION: 1.13.5
    K8S_RELEASE: stable-1.18
    BAZEL_VERSION: 0.23.2
  '1.17':
    CONFIG: '1.17'
    GO_VERSION: 1.13.5
    K8S_RELEASE: stable-1.17
    BAZEL_VERSION: 0.23.2
  '1.16':
    CONFIG: '1.16'
    GO_VERSION: 1.13.5
    K8S_RELEASE: stable-1.16
    BAZEL_VERSION: 0.23.2
  '1.15':
    CONFIG: '1.15'
    GO_VERSION: 1.12.12
    K8S_RELEASE: stable-1.15
    BAZEL_VERSION: 0.23.2

variants:
  experimental:
    CONFIG: experimental
    GO_VERSION: 1.13.6
    K8S_RELEASE: stable
    BAZEL_VERSION: 0.28.1
    UPGRADE_DOCKER: 'true'
  master:
    CONFIG: master
    GO_VERSION: 1.13.6
    K8S_RELEASE: stable
    BAZEL_VERSION: 0.23.2
  '1.18':
    CONFIG: '1.18'
    GO_VERSION: 1.13.6
    K8S_RELEASE: stable-1.18
    BAZEL_VERSION: 0.23.2
  '1.17':
    CONFIG: '1.17'
    GO_VERSION: 1.13.6
    K8S_RELEASE: stable-1.17
    BAZEL_VERSION: 0.23.2
  '1.16':
    CONFIG: '1.16'
    GO_VERSION: 1.13.6
    K8S_RELEASE: stable-1.16
    BAZEL_VERSION: 0.23.2
  '1.15':
    CONFIG: '1.15'
    GO_VERSION: 1.12.12
    K8S_RELEASE: stable-1.15
    BAZEL_VERSION: 0.23.2

Update go version to 1.13.6
[1.18] images/kubekins-e2e: Update go version to 1.13.6
