Managers ID : Introduced variable to declare Managers ID in resource.robot and updated all the scripts in openbmc-test-automation

Changes:
    - Introduced ${MANAGER_ID} variable in resource.robot
    - Replaced all the Managers/bmc to Managers/${MANAGER_ID} across all the scripts
    - Also in data/variables.py updated chassis id for the few redfish uri.

Tested:
     - Ran All The Scripts Successfully

Change-Id: Iff3673aae27657e0799dec5cb94c1651a0cd5d18
Signed-off-by: ganesanb <ganesanb@ami.com>
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/ipmi/test_ipmi_network_verification.robot b/ipmi/test_ipmi_network_verification.robot
index b1d4075..35a0df6 100644
--- a/ipmi/test_ipmi_network_verification.robot
+++ b/ipmi/test_ipmi_network_verification.robot
@@ -95,7 +95,7 @@
     ${lan_config}=  Get LAN Print Dict  ${CHANNEL_NUMBER}
 
     ${ipv4_addresses}=  Redfish.Get Attribute
-    ...  /redfish/v1/Managers/bmc/EthernetInterfaces/${active_channel_config['${CHANNEL_NUMBER}']['name']}
+    ...  /redfish/v1/Managers/${MANAGER_ID}/EthernetInterfaces/${active_channel_config['${CHANNEL_NUMBER}']['name']}
     ...  IPv4Addresses
 
     FOR  ${ipv4_address}  IN  @{ipv4_addresses}