Alerts ".all" property method should work with stream too.

Since window node has [fillPeriod](https://docs.influxdata.com/kapacitor/v1.4/nodes/window_node/#fillperiod) which works as some sort of buffing, so ".all()" property method in alert node should work with stream too.
Thanks

Start by reading the linked window-node fillPeriod documentation and locating the alert node's .all() property behavior for streams. Verify how window buffering affects stream inputs, then define done as making .all() work for stream alerts with coverage for the relevant behavior.

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