Overwrite of png files fails

[bitterbark]

Bug Severity

• [ 1] 1 = Minor problem that does not affect total framework functionality

Describe the bug
Despite setting "overwrite": true, the png files fail to get overwritten, generating a failure code for the entire pod (not to mention an out-of-date png file).

ERROR: Deactivated <#TPSg:30L_cam5301_FAMIP.blocking_neale> due to OSError
('.../MDTF_30L_cam5301_FAMIP_1990_1994/blocking_neale/model/block_freq_anncycle.30L_cam5301_FAMIP.png exists.').

Steps To Reproduce
What steps did you follow to produce the bug
in default_tests.jsonc, set
"overwrite": true
and then run mdtf at least twice (once to generate the png files, the second to fail to overwrite).

This occurs when running the new (not yet incorporated) blocking pod but I don't believe it is limited to that.

Environment
Describe the system environment:

• OS: [e.g. RHEL 7.2]
• Conda version: [the conda info command will provide the installation information]
• branch name and link: [e.g., develop, https://github.com/NOAA-GFDL/MDTF-diagnostics/tree/develop]

Log information and/or terminal output
Copy information from any output logs and/or the terminal that might help with debugging.