Add Team Package - Community Contributions section

Why is this change being made?

This MR adds a Community Contributions to the Package Team page, in the How we work section.

It helps by defining what is a Community Contributions for the Package Team and what are the concrete tasks and points that the assigned Package Team member should pay attention to.

Does this MR meet the acceptance criteria?

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what