Update UX weight definition

Why is this change being made?

As per Retrospective for UX Issue weights, this MR intends to start discussing the refinement of our UX weight definition by providing more details within the description section.

Does this MR meet the acceptance criteria?

Assign to DRI

• Did you assign this change to the correct DRI of the page or information you are changing?

Conformity

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