CLEANUP/MINOR: spec: fix names to match snake case in spec #1018

Job	Run time
generate-specification	1m 4s
generate-models	1m 40s
HAProxy check commit message	0s
golangci-lint	1m 8s
lint-spec	13s
go mod tidy	20s
Build	32s
license-check	29s
Test equal	1m 21s
Tests	53s
e2e on HAProxy (2.1)	53s
e2e on HAProxy (2.3)	48s
e2e on HAProxy (2.4)	50s
e2e on HAProxy (2.5)	52s
e2e on HAProxy (2.7)	49s
e2e on HAProxy (2.2)	50s
e2e on HAProxy (2.6)	51s
e2e on HAProxy (2.8)	50s
	14m 23s

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