Add condition for docker pull operation

By default, when docker plugin is used in pipelines
we always pull image as a separate action. Sometimes it may hurt
i.e. when registry is accessible only with username and password.
This w/a will implement a switch that can enable or disable pull. 

Related-PROD: PROD-31909

Change-Id: I611a1328da4996d839096796e6e148f35eb91763
1 file changed