Update Digital Tactics section with reporting instructions

Why is this change being made?

@lblanchard @krogel @Helenadixon I have added a ROI section under Digital Tactics to include SFDC UTM + Data Studio reporting for clarity and consistency across the FM org. Please feel free to amend as needed!

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
• Assign this change to the correct DRI
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