During definition import, Shovel startup can race with queue startup

[michaelklishin]

Currently a definition file with quorum queues and dynamic Shovels that rely on those queues and use queue destination can be imported with confusing results: the queues will be imported concurrently with the shovels, and the shovels may end up "winning" the race and declare their queues. Due to #2798, there is no way to make a dynamic Shovel declare a quorum queue, so the queues can end up being of the wrong type.

There are two fundamental solutions that do not tie Shovel startup to the process of definition import in the core:

• Split the definitions into two files, one with the topology and another one with Shovels
• Address Provide a way to specify queue type for dynamic Shovel destination #2798

However, we can move runtime parameter and policy import step after the queue (topology) import step and reduce the likelihood of confusion.