Clean up trigger.go (#1374) with changes from JobID Resolution (#1379)

Problem to solve

I have intentionally developed the two MR !1374 (merged) and !1379 (merged) separately from each other. However, I would now like to incorporate the improvements from !1379 (merged) into the new command glab ci trigger. In principle, the command will be extended by the interactive selection of a job, but above all the code will be simplified. Since the new method getJobID is used.

Proposal

also use ciutils.GetJobId in NewCMDTrigger

Further details

I actually want to clean up my code that was created by the separation of MR.

Links / references

• !1379 (merged)
• !1374 (merged)