minimums:
  chrome: 67
  safari: 11
  firefox: 60
  ie: 12

minimums:
  chrome: 67
  safari: 11
  firefox: 68
  ie: 12

Update browser file to Firefox 68
Update browser file to Firefox 68

This file only manages the warning banner that displays
for customers that are using a browser below the minimum
supported version. We need to bring the banner back for
users of Firefox below version 68. Firefox is already at
version 69 as of this ticket date, and Firefox ESR 60
has an end of life at the end of October; users need
to upgrade before then.

CLOSES: DOC-1107

Test plan:
- Jenkins passes

Change-Id: Ie842b54230cec3d7488d96d0bc11a4db0cb98851
Reviewed-on: https://gerrit.instructure.com/208290
Tested-by: Jenkins
Reviewed-by: Ryan Shaw <ea3cd978650417470535f3a4725b6b5042a6ab59@instructure.com>
QA-Review: Erin Hallmark <2a4b17b11682b229726079a631360cf016a43450@instructure.com>
Product-Review: Erin Hallmark <2a4b17b11682b229726079a631360cf016a43450@instructure.com>
