Update mapping/sustainability.yaml

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Co-authored-by: Duncan Dewhurst <[email protected]>

mapping/sustainability.yaml

@@ -543,7 +543,7 @@
     module: Climate finance
     indicator: Decision-making process
     disclosure format: Identify who approved the climate finance investment in the country (organization, party, role)
-    mapping: 'Project level: Add the organization to the `parties` array and add ''climateFinanceFocalPoint'' to their `.roles` array.'
+    mapping: 'Project level: [Add an organization](../common.md#add-an-organization) for the decision maker and add ''climateFinanceFocalPoint'' to its `.roles` array.
     example: |-
         {
           "parties": [