update intake form of device termination workflow

added two checkboxes that take care of removing config, and cleaning up IPAM made the corresponding steps in the workflow conditional, so they are skipped if unchecked

@simone.spinelli let me know whether this is what you had in mind

gso/translations/en-GB.json

@@ -29,7 +29,9 @@
             "iptrunk_sideB_ae_iface": "Aggregated Ethernet interface name",
             "iptrunk_sideB_ae_geant_a_sid": "GÉANT A-SID",
             "iptrunk_sideB_ae_members": "Aggregated Ethernet member interface names",
-            "iptrunk_sideB_ae_members_descriptions": "Aggregated Ethernet member interface descriptions"
+            "iptrunk_sideB_ae_members_descriptions": "Aggregated Ethernet member interface descriptions",
+            "remove_configuration": "Remove configuration from the device",
+            "clean_up_ipam": "Clean up related entries in IPAM"
         }
     },
     "workflow": {