Replaced campaignPreference with CAMPAIGNS_DEFAULT_PREFERENCE (commons-app#5357)

Co-authored-by: Kwong Yu Zhou <https://github.com/kwong-yu-zhou>
Co-authored-by: Adam Jones <domdomegg+git@gmail.com>

Author: Kwong-Yu-Zhou

app/src/main/java/fr/free/nrw/commons/campaigns/CampaignView.java

@@ -69,7 +69,7 @@ public void setCampaign(final Campaign campaign) {
     @Override public boolean onSwipe(final View view) {
         view.setVisibility(View.GONE);
         ((BaseActivity) getContext()).defaultKvStore
-            .putBoolean(campaignPreference, false);
+            .putBoolean(CAMPAIGNS_DEFAULT_PREFERENCE, false);
         ViewUtil.showLongToast(getContext(),
             getResources().getString(R.string.nearby_campaign_dismiss_message));
         return true;