[JENKINS-47929] Extensible run details tabs

[stuartrowe]

Description

See JENKINS-47929.
Fixing issues reported after #2268 was merged.

Unit/Acceptance Tests
Added additional test for RunDetailsArtifacts component in run-details-artifacts-spec.js.

Submitter checklist

• Link to JIRA ticket in description, if appropriate.
• Change is code complete and matches issue description
• Appropriate unit or acceptance tests or explanation to why this change has no tests
• Reviewer's manual test instructions provided in PR description. See Reviewer's first task below.

Reviewer checklist

• Run the changes and verified the change matches the issue description
• Reviewed the code
• Verified that the appropriate tests have been written or valid explanation given

[stuartrowe]

@olamy I've fixed the issue with my previous version of this change. The new test failures appear to be existing issues on master.

[olamy]

@stuartrowe Thanks!