Make CreateAltAlleleTable task volatile

[rsasch]

Test run here: https://app.terra.bio/#workspaces/gvs-dev/RSA%20-%20GVS%20Quickstart%20V2%20/job_history/7f2307e7-684d-45d7-a4e7-852a666ec440

[codecov]

Codecov Report

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Additional details and impacted files

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