Backend: Add field to JobType for differentiating between a Ci::Bridge and a Ci::Build

Problem

Details of the main problem are noted in the design issue

There needs to be a distinction made coming from the backend to know whether a job is a build or a bridge type as this will help when troubleshooting a pipeline that triggers a downstream to determine which jobs trigger pipelines to decrease the time it takes to get to problem resolution.

Proposal

From a backend perspective, we will add an enum Type to JobType that returns if a job is a Ci::Build or a Ci::Bridge.

Implementation Table

Issue	Issue Link
Design: Differentiate trigger jobs from regular jobs in the pipeline graph and mini pipeline graph	#340194 (closed)
Backend: Differentiate trigger jobs from regular jobs in the UI	👈 You are here
Frontend: Differentiate trigger jobs from regular jobs in the pipeline graph	#356330 (closed)
Frontend: Differentiate trigger jobs from regular jobs in the mini- pipeline	#356331

Links/References