Refactor check if a service exists to a basic GET request check without the stage

[christian-kreuzberger-dtx]

Right now we need to know project, service and stage in order to check whether a service exists:

keptn-jenkins-library/src/sh/keptn/Keptn.groovy

Lines 286 to 299 in 60e4f86

	def keptnProjectServiceExists(Map args) {
	def keptnInit = keptnLoadFromInit(args)
	def getProjectServiceResponse = httpRequest customHeaders: [[maskValue: true, name: 'x-token', value: "${keptnInit['keptn_api_token']}"]],
	httpMode: 'GET',
	responseHandle: 'STRING',
	url: "${keptnInit['keptn_endpoint']}/controlPlane/v1/project/${keptnInit['project']}/stage/${keptnInit['stage']}/service/${keptnInit['service']}",
	validResponseCodes: "100:404",
	ignoreSslErrors: true
	echo "Response from get project service: " + getProjectServiceResponse.content
	return (getProjectServiceResponse.status == 200)
	}

This is a known limitation in the Keptn API.

Definition of Done

• Use a basic GET Endpoint without the stagename to check whether a service exists

Depends on keptn/TBD