Improve pipelines table spacing, add triggerer column

What does this MR do?

Improve the spacing of columns and information in the pipelines table, mainly prevent overlap between the triggerer avatar and the commit author avatar

• Separate out the pipeline triggerer into its own column and prevent it from overlapping with or being confused with the commit author
• Allow contents in the Commit column to wrap
• Adjust column widths:
  • Status: 10% -> 10%
  • Pipeline: 15% -> split into 10% for Pipeline and 10% for Triggerer
  • Commit: 20% -> 20%
  • Stages: 20% -> 15%
  • Time ago: 15% -> 15%
  • Actions: 20% -> 20%

	Before	After
Full width
Narrow width

What are the relevant issue numbers?

#58105 (closed), #38802 (closed), #35936 (moved), #58342 (moved)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• Security reports checked/validated by reviewer

Closes #58105 (closed), #38802 (closed)