Add allowShortCircuit exception for no-unused-expressions
Add allowShortCircuit exception for no-unused-expressions

test plan:
  - node ./node_modules/.bin/eslint packages/canvas-rce/src/bridge/Bridge.js
    does not generate a warning or error.

Change-Id: I136f9bce39ea9a85999cbd5b244fd9d021b3a123
Reviewed-on: https://gerrit.instructure.com/205915
Reviewed-by: Ryan Shaw <ea3cd978650417470535f3a4725b6b5042a6ab59@instructure.com>
QA-Review: Ryan Shaw <ea3cd978650417470535f3a4725b6b5042a6ab59@instructure.com>
Product-Review: Ryan Shaw <ea3cd978650417470535f3a4725b6b5042a6ab59@instructure.com>
Tested-by: Jenkins

sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms