GraphQL CI API: add job filters [RUN AS-IF-FOSS]

What does this MR do?

This adds new GraphQL features to supply CI build result information.

This adds the edge Pipeline.job to fetch a single job by name. Edges are added from CiJob -> Stage and Stage -> [CiJob]..

Summary of changes:

• Filtering Pipeline.jobs by status
• New fields on CiJob.
• Fetch single job by name or ID with Pipeline.job

Example Query

 query($path: ID!, $name: String) {
   project(fullPath: $path) {
     pipelines(first: 1) {
       nodes {
         jobs(statuses: [SUCCESS]) {
           name duration
         }
         job(name: $name) {
           name
           status
         }
        }
      }
    }
  }

These new features are accessible through any Pipeline node. So the following is also a new query we can express:

query($path: ID!, $mrIID: String, $name: String) {
   project(fullPath: $path) {
     mergeRequest(iid: $mrIID) {
       headPipeline {
         jobs(statuses: [FAILED]) {
           name
         }
       } 
     }
   }
 }

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team