Quickstarter test framework extensions ..

Is your feature request related to a problem? Please describe.

Especially in the context of the release manager - we need two more pieces ...

a) the check for non-existant attachments and
b) the check for other jenkins pipeline runs (e.g. those triggered by RM commits...)

@michaelsauter - I plan on extending the struct already existing with

	// Especially for release manager, but maybe for others, it's important to verify other jobs
	VerifyOtherJenkinsJobs []struct {
		// Name of the job BC, latest run is always taken
		JobName string `json:"jobName"`
		// JSON file defining expected Jenkins stages (relative to "testdata" directory).
		JenkinsStages string `json:"jenkinsStages"`
		// Status the job must be in
		JobStatus string `json:"jobStatus"`
	} `json:"verifyOtherJenkinsJobs"`