Use recently built image instead of latest for src (#2649)
* Use recently built image instead of latest for src
* Recalculate hash to prove it is correct
* Fix mock
* Update mocks
* Only do it if there's a r8.im model
* Suggestions from comments
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Co-authored-by: Nikhil Sinha <nsinha@cloudflare.com>
Co-authored-by: Mark Phelps <209477+markphelps@users.noreply.github.com>
Co-authored-by: mfainberg-cf <mfainberg@cloudflare.com>
