update(lib_image):Adding LIB_IMAGE ENV in node cpu/memory hog experiment (#204)

Signed-off-by: shubhamchaudhary <shubham.chaudhary@mayadata.io>

charts/generic/node-drain/experiment.yaml

@@ -60,6 +60,11 @@ spec:
     - name: TOTAL_CHAOS_DURATION
       value: '60'
 
+    # Provide the LIB here
+    # Only litmus supported
+    - name: LIB
+      value: 'litmus'
+
     # Period to wait before injection of chaos in sec
     - name: RAMP_TIME
       value: ''