release-24.1: roachtest: make failover timeouts less aggressive

[blathers-crl]

Backport 1/1 commits from #132931 on behalf of @nvanbenschoten.

/cc @cockroachdb/release

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Fixes #132830.

This commit increases the timeout for various failover test from 30 minutes to 45 minutes. Each of these tests performs 9 iterations of failover which takes at least 2 minutes per iteration, plus rebalance time and failover time. That gives the test little tolerance for slowness or temporary instability. Since the point of these tests has nothing to do with the timeout, we can afford to be more lenient to avoid flakiness.

Release note: None

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Release justification: test only

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

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  issues or test-only changes.
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[cockroach-teamcity]

This change is