[torchelastic] Set the correct maximum border width
Summary: The diff sets the correct max border delimiters between error sections
Test Plan: Example of the uncontrolled border: https://www.internalfb.com/intern/testinfra/diagnostics/7599824415964133.844424970500348.1625590344/
Reviewed By: kiukchung
Differential Revision: D29636814
fbshipit-source-id: 95465d3150066bff82dc7499bb1c63ea4f5ebc2d
