refs #12442 - generate a fuzzing corpus by extracting code from `testrunner`

[firewave]

[firewave]

I tried to do this via an option. It would be possible to pass this as an internal field via the Settings but it would be problematic to get that into all Settings objects in the tests.

[firewave]

The idea is to have a corpus generated from all our test cases which will generate an artifact which can be pulled from the OSS-Fuzz integration to be used. This will give us a broad spectrum of code.

Some of the files are rather big though and I wonder if we should filter those out since they could provide misleading timeouts and too big inputs. But that could also be handled by specify the maximum input size via a fuzzing CLI parameter.

[sonarqubecloud[bot]]

Quality Gate passed

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0 Accepted issues

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[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud