title: Avoid resetting HikariCP datasource connection pool on property change/refresh
body: <p>I am using spring boot 2 with PCF config server to use centrallized config. My microservice is basic crud rest service. What I noticed is that whenever a property is being changed and http post is being made on "actuator/refresh" endpoint, spring boot 2 drops all connection including active ones and rebuilds the connection pool. How can I avoid this? I am also using spring-boot-starter amqp and cloud bus to notify all my service instance to refresh the properties so it is also happening for http post on "actuator/bus-refresh".</p>
  
  <p>Also to clarify, I didnot change any property related to datasource config, instead I am changing application specific property, so why does spring boot refreshing datasource, I did not understood.</p>