Fix PHP notice on wordpress permissions form

[mattwire]

Overview

Sometimes $params[$role] is not set and you get a PHP notice.

Before

PHP notice if $params[$role] is not set.

After

No PHP notice.

Technical Details

Happened when updating a wordpress role to add additional permissions. Undefined index was "administrator".

Comments

[civibot]

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[eileenmcnaughton]

Thanks @mattwire - seems pretty straight forward