Add an integration test for a config with a negative refspec #7045

Job	Run time
build	1m 14s
check-codebase	15s
check-for-fixups	4s
check-required-label	3s
Integration Tests - git 2.20.0	1m 28s
lint	26s
Integration Tests - git 2.22.5	1m 20s
ci - ubuntu-latest	50s
Integration Tests - git 2.23.0	1m 20s
ci - windows-latest	1m 19s
Integration Tests - git 2.25.1	1m 30s
Integration Tests - git 2.30.8	1m 28s
Integration Tests - git latest	1m 19s
upload-coverage	0s
	12m 36s

Provide feedback