Address flakiness and latency in the Traffic-Based App Rewards integration test

[adetokunbo]

Fixes #6420

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[adetokunbo]

@dfordivam As discussed, I've included the switch to 1sv topology in this PR, now that TBAR bootstrap behavior is more comprehensively tested in #6392. Locally this reduces test wall clock runtime by 27%. There are other obvious stability benefits in the CI environment

[dfordivam]

Looks fine, let's get review from Robert as well

[dfordivam]

Dont forget to revert https://github.com/canton-network/splice/pull/6386/changes
Or add a comment why its ok to keep it removed

[adetokunbo]

Dont forget to revert https://github.com/canton-network/splice/pull/6386/changes Or add a comment why its ok to keep it removed

added a comment

[dfordivam]

Based on the conversation around the ingestion race causing flake, it occurred to me that making this 1 SV might increase the chances of flake. Because the DsoRules gets updated multiple times during round 0 for 4 SV, the DbScanRewardsReferenceStore has a higher chance of observing an archival of contract. With 1 SV the first archival the store sees might be round 0 archival.

[rautenrieth-da]

I'm not yet convinced this will make the test less flaky, but happy to try while we investigate the root cause.

[adetokunbo]

As discussed, we'll continue to monitor this while we investigate the root cause