Allow rolling upgrades for Mirror Farms

Issue Summary

This is reproducible on Data Center: (yes)

Steps to Reproduce

1. Stop Mirror1
2. Upgrade Mirror1
3. Start Mirror1

Expected Results

• Upgraded Mirror1 joins the farm with the other, not-yet-upgraded Mirrors

Actual Results

• Upgraded Mirror1 fails to start and join the farm.
  The below exception is thrown in the upgraded Mirror's atlassian-bitbucket.log file:

  2022-12-01 09:11:43,747 ERROR [spring-startup] c.a.j.s.w.s.JohnsonDispatcherServlet SpringMVC dispatcher [springMvc] could not be started
  org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'crowdAliasDao': Unsatisfied dependency expressed through method 'setSessionFactory' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'hazelcast' defined in class path resource [stash-context.xml]: Invocation of init method failed; nested exception is com.atlassian.stash.internal.cluster.NodePassivationException: The current node has been passivated
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.resolveMethodArguments(AutowiredAnnotationBeanPostProcessor.java:767)
      at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918)
      at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583)
      at javax.servlet.GenericServlet.init(GenericServlet.java:158)
      at java.base/java.lang.Thread.run(Thread.java:829)
      ... 19 frames trimmed
  Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'hazelcast' defined in class path resource [stash-context.xml]: Invocation of init method failed; nested exception is com.atlassian.stash.internal.cluster.NodePassivationException: The current node has been passivated
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1804)
      ... 5 common frames omitted
  

Workaround

• Currently there is no known workaround for this behaviour. A workaround will be added here when available