Upgrade Stackdriver Logging Agent addon image from 1.6.0 to 1.6.8.

Author: qingling128

cluster/gce/config-default.sh

@@ -428,7 +428,7 @@ fi
 # Fluentd requirements
 # YAML exists to trigger a configuration refresh when changes are made.
 FLUENTD_GCP_YAML_VERSION="v3.2.0"
-FLUENTD_GCP_VERSION="${FLUENTD_GCP_VERSION:-0.6-1.6.0-1}"
+FLUENTD_GCP_VERSION="${FLUENTD_GCP_VERSION:-1.6.8}"
 FLUENTD_GCP_MEMORY_LIMIT="${FLUENTD_GCP_MEMORY_LIMIT:-}"
 FLUENTD_GCP_CPU_REQUEST="${FLUENTD_GCP_CPU_REQUEST:-}"
 FLUENTD_GCP_MEMORY_REQUEST="${FLUENTD_GCP_MEMORY_REQUEST:-}"

cluster/gce/config-test.sh

@@ -447,7 +447,7 @@ fi
 # Fluentd requirements
 # YAML exists to trigger a configuration refresh when changes are made.
 FLUENTD_GCP_YAML_VERSION="v3.2.0"
-FLUENTD_GCP_VERSION="${FLUENTD_GCP_VERSION:-0.6-1.6.0-1}"
+FLUENTD_GCP_VERSION="${FLUENTD_GCP_VERSION:-1.6.8}"
 FLUENTD_GCP_MEMORY_LIMIT="${FLUENTD_GCP_MEMORY_LIMIT:-}"
 FLUENTD_GCP_CPU_REQUEST="${FLUENTD_GCP_CPU_REQUEST:-}"
 FLUENTD_GCP_MEMORY_REQUEST="${FLUENTD_GCP_MEMORY_REQUEST:-}"

cluster/gce/gci/configure-helper.sh

@@ -2426,7 +2426,7 @@ function setup-fluentd {
   fluentd_gcp_yaml_version="${FLUENTD_GCP_YAML_VERSION:-v3.2.0}"
   sed -i -e "s@{{ fluentd_gcp_yaml_version }}@${fluentd_gcp_yaml_version}@g" "${fluentd_gcp_yaml}"
   sed -i -e "s@{{ fluentd_gcp_yaml_version }}@${fluentd_gcp_yaml_version}@g" "${fluentd_gcp_scaler_yaml}"
-  fluentd_gcp_version="${FLUENTD_GCP_VERSION:-0.6-1.6.0-1}"
+  fluentd_gcp_version="${FLUENTD_GCP_VERSION:-1.6.8}"
   sed -i -e "s@{{ fluentd_gcp_version }}@${fluentd_gcp_version}@g" "${fluentd_gcp_yaml}"
   update-daemon-set-prometheus-to-sd-parameters ${fluentd_gcp_yaml}
   start-fluentd-resource-update ${fluentd_gcp_yaml}