BUG/MINOR: http-request: fix enum for default-errorfile in return action #451

Job	Run time
generate-models	1m 14s
generate-specification	46s
HAProxy check commit message	0s
go mod tidy	10s
golangci-lint	1m 23s
lint-spec	7s
Build	36s
Tests	20s
e2e on HAProxy (2.1)	47s
e2e on HAProxy (2.2)	56s
e2e on HAProxy (2.3)	39s
e2e on HAProxy (2.4)	52s
e2e on HAProxy (2.5)	45s
e2e on HAProxy (2.6)	48s
e2e on HAProxy (2.7)	51s
	10m 14s

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