Automatic merge from submit-queue
fixes invalid null selector issue in sysdig example yaml
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**What this PR does / why we need it**:
Using the file DaemonSet yaml found in the example repo you get the following error upon import:
```
$ kubectl create -f sysdig.yml
The DaemonSet "sysdig-agent" is invalid.
spec.template.metadata.labels: Invalid value: null: `selector` does not match template `labels`
```
This PR fixes this issue.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
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```release-note
```
* Corrected name label metadata for Sysdig example.
Before this change this example would result in:
$ kubectl create -f sysdig.yml
The DaemonSet "sysdig-agent" is invalid.
spec.template.metadata.labels: Invalid value: null: `selector` does not match template `labels`
Di Xu