Feature dtcenter/MET#2796 develop - Fix error log artifact creation

[georgemccabe]

I had to include complicated logic to check if any jobs that save error logs ran successfully to determine if error log artifacts should be merged.

Pull Request Testing

• [X] Describe testing already performed for these changes:
  

Ran a few test runs to ensure correct behavior occurs: https://github.com/dtcenter/METplus/actions/runs/7659713325 - doesn't run merge because no cases had errors https://github.com/dtcenter/METplus/actions/runs/7661855137 - some use cases failed and error_logs was created https://github.com/dtcenter/METplus/actions/runs/7661220745 - all use case succeeded but had diffs - no error_logs should be created/merged

• [X] Recommend testing for the reviewer(s) to perform, including the location of input datasets, and any additional instructions:
  

Review code changes

• [X] Do these changes include sufficient documentation updates, ensuring that no errors or warnings exist in the build of the documentation? [Yes]

• [X] Do these changes include sufficient testing updates? [Yes]

• [X] Will this PR result in changes to the test suite? [No]
  

• [x] Please complete this pull request review by 1/26/2024.
  

[coveralls]

Pull Request Test Coverage Report for Build 7662047088

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 90.762%

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Totals
Change from base Build 7645730422:	0.0%
Covered Lines:	8508
Relevant Lines:	9374

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💛 - Coveralls

[georgemccabe]

The logs are already stored in the output for each use case group. It was cumbersome to have to download the full output for a use case group to get the logs for a single failure, so I set up logic to copy over logs for use cases that have any errors to create a separate artifact that is smaller in size and easier to download.