Update to PE planning process to allow better team commitments

Why is this change being made?

Currently @jheimbuck_gl and @carolinesimpson are committing on behalf of the team to Deliverables. As a team we are not meeting these Deliverables. This adjustment should allow engineers to take more ownership over the commitment and have a greater say in how much work we are committing to finish. Since each engineer is the best judge of their capacity, this will hopefully allow for more accurate planning.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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