Merge pull request #47545 from ixdy/update-1.7-images

Automatic merge from submit-queue (batch tested with PRs 47492, 47542, 46800, 47545, 45764)

Update addons with upstream CVE fixes

**What this PR does / why we need it**: refreshes the cluster-proportional-autoscaler, metadata-proxy, and fluentd-gcp addons with new base images with fixes for the following vulnerabilities:
* CVE-2016-4448
* CVE-2016-8859
* CVE-2016-9841
* CVE-2016-9843
* CVE-2017-9526

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: x-ref #47386, though there are still a few images left to update

**Release note**:

```release-note
Update cluster-proportional-autoscaler, metadata-proxy, and fluentd-gcp addons with fixes for CVE-2016-4448, CVE-2016-8859, CVE-2016-9841, CVE-2016-9843, and CVE-2017-9526.
```

/cc @timstclair @MrHohn @Q-Lee @crassirostris

cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml

@@ -31,7 +31,7 @@ spec:
     spec:
       containers:
       - name: autoscaler
-        image: gcr.io/google_containers/cluster-proportional-autoscaler-amd64:1.1.2
+        image: gcr.io/google_containers/cluster-proportional-autoscaler-amd64:1.1.2-r2
         resources:
             requests:
                 cpu: "20m"

cluster/addons/fluentd-gcp/fluentd-gcp-ds.yaml

@@ -27,7 +27,7 @@ spec:
       hostNetwork: true
       containers:
       - name: fluentd-gcp
-        image: gcr.io/google-containers/fluentd-gcp:2.0.5
+        image: gcr.io/google-containers/fluentd-gcp:2.0.6
         # If fluentd consumes its own logs, the following situation may happen:
         # fluentd fails to send a chunk to the server => writes it to the log =>
         # tries to send this message to the server => fails to send a chunk and so on.

cluster/addons/metadata-proxy/gce/metadata-proxy.yaml

@@ -27,7 +27,7 @@ spec:
       dnsPolicy: Default
       containers:
       - name: metadata-proxy
-        image: gcr.io/google-containers/metadata-proxy:0.1
+        image: gcr.io/google-containers/metadata-proxy:0.1.1
         imagePullPolicy: Always
         securityContext:
           privileged: true