Fix pipeline schedule style issues

What does this MR do?

• Removing the extra borderline between the tabs and the schedule pipelines table.
• Fixing the alignment issue with SVGs on the schedule pipelines table.

What are the relevant issue numbers?

#52925 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• 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.

Closes #52925 (closed)