Fixed bug with parties without articles

These parties are now no longer sent to the template
It previously (before moving data code) did get sent,
but it did not get used in final render either

This mainly fixes things in the Netherlands watchpigeon page currently

src/4-watchpigeon/watchpigeon.11tydata.js

@@ -45,7 +45,7 @@ export default function (configData) {
 
     areas.forEach((areaId) => {
         // -- Get area data
-        const areaParties = AFAWatchpigeonParties.filter(party => party.areas.includes(areaId));
+        let areaParties = AFAWatchpigeonParties.filter(party => party.areas.includes(areaId));
         const areaPartyIds = areaParties.map((party) => party.id)
         const areaArticles =  [];  // Do not add values yet, see below  //AFAWatchpigeonArticles.filter(article => article.responses.find((response) => areaPartyIds.includes(response.party.id)));
         // -- Create output & calculation variables
@@ -89,6 +89,9 @@ export default function (configData) {
             }
         });
 
+        // Filter out areas without any relevant articles
+        areaParties = areaParties.filter(party => Object.keys(pointsByParty).includes(party.id));
+
         // Convert from a possibly negative value to percentages to pass to client-side javascript
         areaParties.map((party) => {
             const partyId = party.id;