Add the test case to verify the Shortest Path First (SPF) Interval.

[vitthalmagadum]

MLF0001-CDN1#show isis summary

IS-IS Instance: 1 VRF: default
Instance ID: 0
System ID: 0100.1020.1114, administratively enabled
Router ID: IPv4: 10.10.201.114
Hostname: MLF0001-CDN1
Multi Topology disabled, not attached
IPv4 Preference: Level 1: 115, Level 2: 115
IPv6 Preference: Level 1: 115, Level 2: 115
IS-Type: Level 2, Number active interfaces: $MLF_ISIS_INTERFACES
Routes IPv4 only
LSP size maximum: Level 1: 1492, Level 2: 1492
Max wait(s) Initial wait(ms) Hold interval(ms)
LSP Generation Interval: 5 50 50
SPF Interval: 5 50 200