Add config to send crash reports which are occurred after kwatch started.

[Warashi]

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I'm always frustrated when kwatch pod is restarted because many crash reports are resent to Slack.

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Add config to send crash reports which are occurred after kwatch started.

[blochsbek]

Yeah this is a big one, def need.

[blochsbek]

Since it already grabs the time that kwatch starts, can it just only pull things after that "time"....