add role="tabpanel" to .panel-collapse to improve accessibility
add role="tabpanel" to .panel-collapse to improve accessibility

Refs #13555.
Per https://github.com/paypal/bootstrap-accessibility-plugin/blob/master/README.md#collapse
Credit: https://github.com/paypal/bootstrap-accessibility-plugin

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ammula88/bootstrap,ammula88/bootstrap,ammula88/bootstrap,ammula88/bootstrap