MapWithAISourceReader#getBounds *must* return a modifiable list

Also, add @Territories annotation to a test that needed it

Signed-off-by: Taylor Smock <tsmock@meta.com>

src/main/java/org/openstreetmap/josm/plugins/mapwithai/io/mapwithai/MapWithAISourceReader.java

@@ -131,8 +131,8 @@ public class MapWithAISourceReader extends CommonSourceReader<List<MapWithAIInfo
                     CountryUtils.getCountryShape(country.getKey()).ifPresent(bounds::add);
                 }
             }
-            return Collections.unmodifiableList(bounds);
+            return bounds;
         }
-        return Collections.emptyList();
+        return new ArrayList<>();
     }
 }

src/test/unit/org/openstreetmap/josm/plugins/mapwithai/gui/download/MapWithAIDownloadSourceTypeTest.java

@@ -14,6 +14,7 @@ import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.RegisterExtension;
 import org.openstreetmap.josm.data.Bounds;
 import org.openstreetmap.josm.plugins.mapwithai.backend.MapWithAIDataUtilsTest;
+import org.openstreetmap.josm.plugins.mapwithai.testutils.annotations.Territories;
 import org.openstreetmap.josm.plugins.mapwithai.testutils.annotations.Wiremock;
 import org.openstreetmap.josm.testutils.JOSMTestRules;
 import org.openstreetmap.josm.testutils.annotations.BasicPreferences;
@@ -21,6 +22,7 @@ import org.openstreetmap.josm.testutils.annotations.BasicPreferences;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 
 @BasicPreferences
+@Territories
 @Wiremock
 class MapWithAIDownloadSourceTypeTest {
     @RegisterExtension