Increase Min/Max cloud run instances

[dividehex]

    Recently, the Min/Max cloud run instances had been reduced in
    an attempt to fix the failure causing the stale apps.yml data.
    This commit increases the min instances to 1 for dev and 2 for
    staging and prod.  The max is set to 3 for all 3 environments.

    This also adjusts the gunicorn async workers to 3 which is based
    on the fact, instances for all environments are set to 1vCpu.
    Where n = vCpus, we get 2n + 1 as a basis for setting the
    workers.  This can be adjust in the future if we ever change the
    number of vCpus per instance.

    Other things:
    * Remove some unused ENVs
    * Remove max-requests and max-requests-jitter

[gcoxmoz]

Addresses the startup concerns from #501, tuning makes sense across the envs, looks right.