Remove redundant units in axis labels

What does this MR do?

Fixes the axis labels to remove redundancy. Namely:

• Latency (ms) (ms)
• Requests / sec (req / sec)

What are the relevant issue numbers?

Closes #56412 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• 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