Fix ERR test.

[fischer-ncar]

Description of changes

Need to write restarts at the end of the run for ERR tests.

Specific notes

Are changes expected to change answers? bfb

Testing performed

ERR_Ln9.ne16pg3_ne16pg3_mt232.FHISTC_LTso.derecho_intel.cam-outfrq9s_bwic
ERR_Ld5.ne30pg3_t232.B1850C_LTso.derecho_gnu.allactive-defaultio
ERR_Ld7.f10_f10_mg37.IHistClm60BgcCrop.derecho_gnu.clm-default
ERR_Ld7.f10_f10_mg37.IHistClm60BgcCrop.derecho_gnu.drv-interim_restart

[fischer-ncar]

@briandobbins @billsacks since Jim is out this week, can either one of you review this PR.

Thanks

[billsacks]

@fischer-ncar - can you explain this change? In your description, you say, "Need to write restarts at the end of the run for ERR tests." But my understanding of the code change is that it does the opposite - i.e., skips writing restart files at the end of the run. Can you clarify the intent of the change, and also why this change is needed? I also want to confirm that this isn't circumventing some aspect of the robustness of this test - e.g., the robustness added by @jedwards4b in ESMCI/cime#4829: I'm wondering if what's really needed is a fix to some logic. I want to clarify that I don't understand the intent of this test well enough to know one way or the other, but just want to better understand the rationale / justification for this change before approving.