Limit RTAMO attribution to www referrals

[muffinresearch]

Description

Ignore attribution for RTAMO if the referral wasn't from www.mozilla.org , using a referer header check.

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Success Criteria

• RTAMO attribution should be present if the user was referred by www.mozilla.org and all other validation is successful.
• RTAMO attribution should be ignored if the user did not start on www.mozilla.org.

[muffinresearch]

@moz-astults Hi, as this is a dependency of other work we need to carry out on AMO, would it be possible to get a rough idea of when this might be worked on? Also please let me know if you have any questions or need additional context.

[moz-astults]

@muffinresearch I am hoping to start looking into this tomorrow or early next week. I'll definitely reach out on slack if I need more context. Thanks!