If historical data is enough, a single stream detector takes 1 interval for cold start to be triggered + 1 interval for the state document to be updated. Similar to single stream detectors, HCAD cold start needs 2 intervals and one more interval to make sure an entity appears more than once. So HCAD needs three intervals to complete cold starts. Long initialization is the single most complained problem of AD. This PR reduces both single stream and HCAD detectors' initialization time to 1 minute by
* delaying real time cache update by one minute when we receive ResourceNotFoundException in single stream detectors or when the init progress of HCAD real time cache is 0. Thus, we can finish the cold start and writing checkpoint one minute later and update the state document accordingly. This optimization saves one interval to wait for the state document update.
* disable the door keeper by default so that we won't have to wait an extra interval in HCAD.
* trigger cold start when starting a real time detector. This optimization saves one interval to wait for the cold start to be triggered.

Testing done:
* verified the cold start time is reduced to 1 minute.
* added tests for new code.

Signed-off-by: Kaituo Li <[email protected]>

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Signed-off-by: Kaituo Li <[email protected]>

Signed-off-by: Kaituo Li <[email protected]>

… version' under JDK 16+

Signed-off-by: Kaituo Li <[email protected]>