extra tests for the tie break merge option

[tantaman]

trafficstars

[tantaman]

@jeromegn - the db version seems to keep moving forward even when the merge is a no-op.

https://github.com/vlcn-io/cr-sqlite/pull/419/commits/aa9a9b03af41772eaee8befdcd7dd160530c1f04

db1 version goes from 2 to 3. It shouldn't move in the second print.

[jeromegn]

Hmm, what could that be? Is the site_id comparison always true in the new logic?

[jeromegn]

Can probably close this one now, fused in #422