tests: change execution config and update doc

integration-tests/README.md

@@ -27,7 +27,17 @@ folder and give it the extension `.feature`.
 
 Read in the sections below which users are available and which operations you can write.
 
- [Cucumber Rust Book]
+If you want to write things that are not yet interpreted, consider adding the `@allow.skipped` tag above your script:
+
+```gherkin
+Feature: My awesome feature
+
+  @allow.skipped
+  Scenario: If something like this happens, then we should observe that
+    Given Something
+    When Something's happening
+    Then We should observe that
+```
 
 ### Test users
 

integration-tests/tests/cucumber_tests.rs

@@ -148,5 +148,8 @@ async fn current_ud_amount_should_be(
 async fn main() {
     //env_logger::init();
 
-    DuniterWorld::run("features").await
+    DuniterWorld::cucumber()
+		.fail_on_skipped()
+		.max_concurrent_scenarios(4)
+		.run("features").await;
 }