310 eliminate pair support from khiopsregressor #820

Job	Run time
check-khiops-integration-on-windows	3m 54s
run (3.8)	8m 52s
run (3.9)	9m 9s
check-khiops-integration-on-linux (ubuntu22.04)	1m 44s
run (3.10)	9m 4s
check-khiops-integration-on-linux (rocky8)	2m 15s
run (3.11)	8m 49s
check-khiops-integration-on-linux (rocky9)	2m 25s
run (3.12)	8m 54s
run (3.13)	9m 3s
	1h 4m 9s

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