Remove Contrib references

Co-authored-by: Matti Schneider <[email protected]>

Author: Cli4d

content/reference/declaration.en.md

@@ -6,7 +6,7 @@ title: "Declaration"
 
 ## Tracking new terms
 
-Tracking terms is done by _declaring_ them and the service they are associated with. Such a declaration is achieved by editing JSON files in the [`declarations`](https://github.com/OpenTermsArchive/contrib-declarations/tree/main/declarations) folder.
+Tracking terms is done by _declaring_ them and the service they are associated with in a collection. Declarations are found in JSON files in the `declarations` folder of the collection.
 
 Before adding new terms, open the [`declarations`](https://github.com/OpenTermsArchive/contrib-declarations/tree/main/declarations) folder and check if the service you want to track terms for is already declared. If a JSON file with the name of the service is already present, you can jump straight to [declaring terms](#declaring-terms). Otherwise, keep reading!