Add scream-prognostic-run workflow

[elynnwu]

Build scream docker image weekly using scheduled pipeline and add scream run commands.

Added public API:

• scream_run is a new command line function as part of the scream_run package
  • includes prepare-config, write-rundir, and execute

Significant internal changes:

• Added CircleCI weekly scheduled pipeline, can be manually triggered by passing run-weekly-workflow as true

• Added prognostic_scream_run dockerfile, combining CIME and scream docker from the scream repo

  • During the docker build process, we pre-compile two scream executables, ne30pg2 with 16 and 180 cores

• [x] Tests added

Coverage reports (updated automatically):