Fixed bug in tests

[ludvigla]

Description

Minor fix in test for RunDPA with parallel processing.

Fixes: exe-1515

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue).
• This change requires a documentation update.

PR checklist:

• This comment contains a description of changes (with reason).
• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• I have checked my code and documentation and corrected any misspellings.
• I have run R CMD check on the package and it passes without errors or warnings (notes can be acceptable if motivated)
• I have documented any significant changes to the code in CHANGELOG.md