fix: make UNSPECIFIED protocol pass validation #5142

Job	Run time
Get files changed and conditionally skip CI	45s
Setup	9s
Generate Envoy Job Matrices	9s
dev-build / build	1m 21s
compatibility-integration-test	8m 39s
nomad-integration-test (v1.3.3)	1m 6s
nomad-integration-test (v1.2.10)	43s
nomad-integration-test (v1.1.16)	44s
vault-integration-test (1.14.1)	2m 15s
vault-integration-test (1.13.5)	2m 34s
vault-integration-test (1.12.9)	2m 18s
vault-integration-test (1.11.12)	2m 17s
envoy-integration-test (1.27.0, server, case-wasm\|case-property-override\|case-cross-peers-http-ro...	5m 8s
envoy-integration-test (1.27.0, server, case-api-gateway-tcp-conflicted\|docs\|case-cfg-resolver-fe...	5m 34s
envoy-integration-test (1.27.0, server, case-terminating-gateway-simple\|case-cfg-resolver-cluster...	6m 0s
envoy-integration-test (1.27.0, server, case-cfg-resolver-subset-redirect\|case-zipkin)	1m 53s
envoy-integration-test (1.27.0, client, case-wasm\|case-property-override\|case-cross-peers-http-ro...	6m 7s
envoy-integration-test (1.27.0, client, case-api-gateway-tcp-conflicted\|docs\|case-cfg-resolver-fe...	4m 46s
envoy-integration-test (1.27.0, client, case-terminating-gateway-simple\|case-cfg-resolver-cluster...	6m 12s
envoy-integration-test (1.27.0, client, case-cfg-resolver-subset-redirect\|case-zipkin)	1m 42s
test-integrations-success	1s
	1h 0m 23s

Provide feedback