Fix shouldAttachEngineToActivity default value

[shts]

shouldAttachEngineToActivity defalut value is true. but this implementation could return false. if user doesnt set value, it should return default value true.

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[chinmaygarde]

@shts Can you please address the guidance of the bots before we can continue.

[johnmccutchan]

I don't understand what bug this PR is addressing.

[chinmaygarde]

Closing this as stale. Please re-open once progress can be made.