Update golden images to use dataSources

Auto-update boot sources introduce a new CRD - dataSources.
Common templates reference dataSources as pointers to actual
golden images PVCs which will be cloned for the VM.

Require:
#230

Author: rnetser

ocp_resources/data_source.py

@@ -0,0 +1,42 @@
+from ocp_resources.resource import NamespacedResource
+
+
+class DataSource(NamespacedResource):
+    """
+    DataSource object
+    """
+
+    api_group = NamespacedResource.ApiGroup.CDI_KUBEVIRT_IO
+
+    def __init__(
+        self,
+        name=None,
+        namespace=None,
+        client=None,
+        source=None,
+        teardown=True,
+        yaml_file=None,
+    ):
+        super().__init__(
+            name=name,
+            namespace=namespace,
+            client=client,
+            teardown=teardown,
+            yaml_file=yaml_file,
+        )
+        self.source = source
+
+    def to_dict(self):
+        res = super().to_dict()
+        if self.yaml_file:
+            return res
+
+        res.update(
+            {
+                "spec": {
+                    "source": self.source,
+                },
+            }
+        )
+
+        return res