Fix regressing caused by merged PR

src/main/java/ca/uhn/fhir/jpa/starter/HapiProperties.java

@@ -10,6 +10,7 @@ import org.hibernate.search.elasticsearch.cfg.ElasticsearchIndexStatus;
 import org.hibernate.search.elasticsearch.cfg.IndexSchemaManagementStrategy;
 import org.jetbrains.annotations.NotNull;
 
+import javax.annotation.Nonnull;
 import java.io.FileInputStream;
 import java.io.InputStream;
 import java.util.Arrays;
@@ -331,6 +332,7 @@ public class HapiProperties {
         return HapiProperties.getProperty(ALLOWED_BUNDLE_TYPES, "");
     }
 
+    @Nonnull
     public static Set<String> getSupportedResourceTypes() {
         String[] types = defaultString(getProperty("supported_resource_types")).split(",");
         return Arrays.stream(types)

src/main/java/ca/uhn/fhir/jpa/starter/JpaRestfulServer.java

@@ -67,8 +67,8 @@ public class JpaRestfulServer extends RestfulServer {
         .getAttribute("org.springframework.web.context.WebApplicationContext.ROOT");
     // Customize supported resource types
     Set<String> supportedResourceTypes = HapiProperties.getSupportedResourceTypes();
-    
-    if (!supportedResourceTypes.contains("SearchParameter")) {
+
+    if (!supportedResourceTypes.isEmpty() && !supportedResourceTypes.contains("SearchParameter")) {
         supportedResourceTypes.add("SearchParameter");
     }