enable bank sim only dag and improve plots

The current status of manifold dags would generate the template bank and run the bank sim in one dag. There would be cases where the manifold template bank already exists and one wants to run just the bank sim dag. This MR enables one to run just the bank sim dag by running singularity exec <SINGULARITY IMAGE> manifold_cbc_bank_test_dag --singularity-image <SINGULARITY IMAGE> name_of_config.yaml. The bank sim only dag name would be manifold_cbc_bank_test.dag so one can launch the dag with condor_submit_dag manifold_cbc_bank_test.dag.

Plots have been revised. Examples are in plots. (This bank sim and the plots were generated using the branch this MR is trying to merge into main.