Revert "handle react discussions in discussion_topic#show"
Revert "handle react discussions in discussion_topic#show"

This reverts commit ec2560d9c68f0a00de813e8bb414a76b46d65627.

Reason for revert: causing 500's on prod

Change-Id: Icf1657cff88e8c94c76f10ee6e43e5bbabe921a4
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/267073
Reviewed-by: Omar Soto-Fortuño <2ca100155bc0669318a7e6f3850629c7667465e1@instructure.com>
Reviewed-by: Caleb Guanzon <54fa1f30d451e4f3c341a8f3c47c9215fd0be9c6@instructure.com>
Reviewed-by: Weston Dransfield <e9203059795dc94e28a8831c65eb7869e818825e@instructure.com>
QA-Review: Omar Soto-Fortuño <2ca100155bc0669318a7e6f3850629c7667465e1@instructure.com>
QA-Review: Caleb Guanzon <54fa1f30d451e4f3c341a8f3c47c9215fd0be9c6@instructure.com>
Product-Review: Omar Soto-Fortuño <2ca100155bc0669318a7e6f3850629c7667465e1@instructure.com>
Product-Review: Caleb Guanzon <54fa1f30d451e4f3c341a8f3c47c9215fd0be9c6@instructure.com>
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>

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