Runner type CSS cleanup

What does this MR do?

This change removes unused CSS to display the runner type as blue or green. This was replaced by info/success badges respectively.

Related MR where those classes were removed form the markup: !59005 (merged)

Screenshots (strongly suggested)

Related screen (no changes)

Does this MR meet the acceptance criteria?

Conformity

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  • I have included a changelog entry.
  • I have not included a changelog entry because this is not a user facing change.
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Security

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Related to #327199 (closed)