Infoless deploy test timestamp test

[brianmcmichael]

Fixes issue described at #166 (review) without need for timestamp.

[brianmcmichael]

This loosens up the test a little bit by not requiring that we're on the exact block a spell has been deployed on, but that it will still expire within the expiration threshold. Since this is the only test that needed the exact timestamp I think it still provides sufficient assurance that the spell expiry is ok.

[iamchrissmith]

This is fine for me since it still proves we didn't create a long lived spell, but it does take away the protection of a short lived spell. I don't think there is a risk there, so just noting it

[The-Arbiter]

Change is OK

[naszam]

@brianmcmichael I think we can close this PR as timestamp will remain for now and consumed by the spell automation scripts and integration tests

[DaiFoundation-DevOps]

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