core: disable controller runtime metrics server

[Madhu-1]

Description of your changes:

As we are not using the controller runtime metrics we dont even need to start the server as it just uses extra resources and its not much useful.

• Before disabling the metrics port

sh-4.4# netstat -plnt
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp6       0      0 :::8080                 :::*                    LISTEN      1/rook              
sh-4.4# 

• After Disabling the metrics port

sh-4.4# netstat -plnt
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
sh-4.4# 

Which issue is resolved by this Pull Request:
Resolves #

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