Fix advertised token for source

[eileenmcnaughton]

Overview

Fix advertised token for source

Before

Advertised token is {contribution.contribution_source}
Preferred token is {contribution.source}

• only the preferred works in action schedules
• both work for send letter action

After

Preferred is advertised, tests prove functionality is not affected (scheduled reminders were already tests so tests added to the legacy token flow)

Technical Details

Comments

[civibot]

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[eileenmcnaughton]

test this please