Dashboard hunter not working (#337)

* Fix dashboard hunter regression
Fix #336.
Add tests for dashboard hunter

Co-authored-by: Yehuda Chikvashvili <yehudaac1@gmail.com>

tests/hunting/test_dashboard.py

@@ -0,0 +1,37 @@
+import json
+
+from types import SimpleNamespace
+from requests_mock import Mocker
+from kube_hunter.modules.hunting.dashboard import KubeDashboard
+
+
+class TestKubeDashboard:
+    @staticmethod
+    def get_nodes_mock(result: dict, **kwargs):
+        with Mocker() as m:
+            m.get("http://mockdashboard:8000/api/v1/node", text=json.dumps(result), **kwargs)
+            hunter = KubeDashboard(SimpleNamespace(host="mockdashboard", port=8000))
+            return hunter.get_nodes()
+
+    @staticmethod
+    def test_get_nodes_with_result():
+        nodes = {"nodes": [{"objectMeta": {"name": "node1"}}]}
+        expected = ["node1"]
+        actual = TestKubeDashboard.get_nodes_mock(nodes)
+
+        assert expected == actual
+
+    @staticmethod
+    def test_get_nodes_without_result():
+        nodes = {"nodes": []}
+        expected = []
+        actual = TestKubeDashboard.get_nodes_mock(nodes)
+
+        assert expected == actual
+
+    @staticmethod
+    def test_get_nodes_invalid_result():
+        expected = None
+        actual = TestKubeDashboard.get_nodes_mock(dict(), status_code=404)
+
+        assert expected == actual