docs: add new document for hello operator #778

Job	Run time
deployment (static, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta3/emqxenterprise-slim.yaml)	4m 0s
deployment (static, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta3/emqxenterprise-full.yaml)	3m 58s
deployment (static, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta4/emqxenterprise-slim.yaml)	4m 3s
deployment (static, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta4/emqxenterprise-full.yaml)	3m 37s
deployment (static, EMQX, emqx, config/samples/emqx/v2alpha1/emqx-slim.yaml)	3m 27s
deployment (static, EMQX, emqx, config/samples/emqx/v2alpha1/emqx-full.yaml)	4m 11s
deployment (static, EMQX, emqx, config/samples/emqx/v2beta1/emqx-slim.yaml)	3m 26s
deployment (static, EMQX, emqx, config/samples/emqx/v2beta1/emqx-full.yaml)	4m 13s
deployment (helm, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta3/emqxenterprise-slim.yaml)	3m 41s
deployment (helm, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta3/emqxenterprise-full.yaml)	3m 29s
deployment (helm, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta4/emqxenterprise-slim.yaml)	3m 32s
deployment (helm, EmqxEnterprise, emqx-ee, config/samples/emqx/v1beta4/emqxenterprise-full.yaml)	3m 29s
deployment (helm, EMQX, emqx, config/samples/emqx/v2alpha1/emqx-slim.yaml)	3m 25s
deployment (helm, EMQX, emqx, config/samples/emqx/v2alpha1/emqx-full.yaml)	3m 57s
deployment (helm, EMQX, emqx, config/samples/emqx/v2beta1/emqx-slim.yaml)	3m 14s
deployment (helm, EMQX, emqx, config/samples/emqx/v2beta1/emqx-full.yaml)	3m 43s
	59m 25s

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