check_if_signed: Get source branch if not set
Work around CI_MERGE_REQUEST_SOURCE_BRANCH_NAME issue in Gitlab.com CI. See !929 (closed)
Checklist
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Code modified for feature -
Test suite updated with functionality tests -
Test suite updated with negative tests -
Documentation updated / NEWS entry present (for non-trivial changes)
Reviewer's checklist:
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Any issues marked for closing are addressed -
There is a test suite reasonably covering new functionality or modifications -
Function naming, parameters, return values, types, etc., are consistent and according to CONTRIBUTION.md
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This feature/change has adequate documentation added -
No obvious mistakes in the code