Show warning to setup aws keys first

[msoni11]

Our plugin is purely dependent on AWS rekognition proctoring. If the correct settings are not in place, it will throw error during the quiz. We need to block that at initial level only if AWS params are not set under settings.

[jainkavita31]

@msoni11 i commit the changes.. please let me know if need any changes.

[msoni11]

We can't expose keys openly in browser. We need to think about another solution. I think https://github.com/taketwotech/moodle-quizaccess_quizproctoring/blob/master/rule.php#L240 is right place for that check.

[jainkavita31]

@msoni11 apply solution on prevent_access function. we need to show warning messages to admin and student.. please have a look..

[jainkavita31]

@msoni11 done . Add link for AWS configuration

[msoni11]

Thanks.