Added a URL discussing approvals for resetting max seats in SaaS

Why is this change being made?

When support is asked to adjust the max users value on an existing group in SaaS we require approval from leadership in the Sales organization. The level at which this approval is required isn't clear as it stands now. I've changed part of the wording to be a URL that refers back to the documentation that elaborates further on what level of management needs to be involved in this change.

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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