Make details summary examples consistent
Make details summary examples consistent

- Use a grey left hand border (.panel-indent) within details summary to
associate the revealed content with the summary.

alphagov/govuk_elements,alphagov/govuk_elements,gavboulton/govuk_elements,gavboulton/govuk_elements,joelanman/govuk_elements,alphagov/govuk_elements,TFOH/govuk_elements,gavboulton/govuk_elements,alphagov/govuk_elements,TFOH/govuk_elements,gavboulton/govuk_elements,joelanman/govuk_elements