Remove usage of non-conformant font-size 20

What does this MR do?

As part of #36857, this MR removes the usage of font-size-20.

Does this MR meet the acceptance criteria?

Conformity

• Code review guidelines
• Merge request performance guidelines
• Style guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.