Updating job executor scope for JTBD mapping

Why is this change being made?

When a category moves up in maturity level, the key executors for the JTBDs associated with it should be re-looked at to make it more inclusive of the decision making personas to focused could shift from shipping the essential features to making the offerings more desirable.

(This MR adds a note to the JTBD mapping instruction to include the next relevant persona as the core executor considering the maturity level of the category or stage-group.)

There is often a direct connection between required features/functionality and the category's adoption. The more we deliver based on our performer's needs, the more desirable it becomes to organizations to adopt the category/stage/application. Complete and Loveable categories should be looking to solve problems at the intersection of Stages and/or by expanding the scope of their problem and solution area to identify new value. Solving these newly identified and unmet needs enables our marketing and sales counterparts to drive the adoption process while we continue to fuel it. -@andyvolpe

Author Checklist

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